PaxScan 3030CB / 4030CB. Systems & Service Guide

Transcription

1 PaxSca 3030CB / 4030CB Systems & Service Guide P/N Rev. D February 2010

2 Abstract Techical Support The PaxSca 3030CB / 4030CB Systems & Service Guide (P/N 20099) provides referece iformatio ad procedures for usig the Varia PaxSca 3030CB / 4030CB digital imagig subsystem with a basic image processig workstatio ad commuicatios iterface software. If you caot fid iformatio i this user guide, you ca cotact us i several ways: Uited States Varia X-ray Products Phoe 1678 So. Pioeer Rd Phoe Salt Lake City, Ut Fax Europe Varia X-Ray Products Zutphesestraat 160A 6971 ET Brumme The Netherlads Phoe Fax East Asia Varia X-Ray Products 4th MY ARK Nihobashi Bldg Tomizawa-cho Nihobashi,Chuo-ku Tokyo , Japa Phoe Fax Chia Varia X-Ray Products Orietal Plaza Tower W1, Suite East Chag a Aveue Beijig , P.R.Chia Phoe Fax You ca fid more iformatio about Varia Imagig Products o our Website: Click Products ad the Imagig Products. Notice Iformatio i this user guide is subject to chage without otice ad does ot represet a commitmet o the part of Varia to update iformatio. Varia is ot liable for errors cotaied i this guide or for ay damages icurred i coectio with furishig or use of this material. This documet cotais proprietary iformatio protected by copyright. No part of this documet may be reproduced, traslated, or trasmitted without the express writte permissio of Varia Medical Systems, Ic. The PaxSca 3030CB / 4030CB is a Class 1 system per the Stadard for Medical Electrical Equipmet, UL Classified by the Caadia Stadard for Medical Electrical Equipmet, C22.2, No M90. CE Mark Trademarks Varia Medical Systems imagig products are desiged ad maufactured to meet the Low Voltage Directive 73/23/EEC ad EMC 93/42/EEC. The product carries the CE mark through MDD compliace. PaxSca, ad ViVA are trademarks of Varia Medical Systems, Ic. Microsoft is a registered trademark ad Widows is a trademark of Microsoft Corporatio Varia Medical Systems, Ic. All rights reserved. Prited i the Uited States of America. ii

3 CHAPTER SUMMARY Itroductio 1 System Overview 2 Gettig Started 3 Calibratio Procedures 4 PaxSca Applicatio Software 5 ViVA Help 6 System Cofiguratio 7 Commad Processor Hardware Specificatios 8 Safety 9 Maiteace 10 Troubleshootig 11 Techical Support 12 Appedix A - Glossary of Terms A Appedix B- Commad Processor ad Computer Iterface B Appedix C - Calibratio Procedure for 3030CB / 4030CB High DR modes C Appedix D- Multiple Gai Ragig D iii

4 CHAPTER 1 INTRODUCTION...11 CHAPTER 2 SYSTEM OVERVIEW...13 Receptor...15 Amorphous Silico: Features ad Beefits Properties of Amorphous Silico Commad Processor...18 Offset ad Gai Variatios...19 Iteral Power Supply Modes of Operatio Default Mode Image Processig CHAPTER 3 GETTING STARTED Shipmet Cotets Coectig the Cables Mechaical Moutig...26 Receptor Moutig Commad Processor Power O Sequece Establishig Coectio Basic Offset Calibratio Basic Gai Calibratio Image Acquisitio...30 Fluoroscopy - Normal CHAPTER 4 CALIBRATION PROCEDURES...33 Offset Calibratio Gai Calibratio...34 Fluoroscopic Mode Gai Calibratio Defective Pixel Maps Aalog Offset Calibratio...40 Verificatio of Aalog Offset Calibratio CHAPTER 5 PAXSCAN APPLICATION SOFTWARE...43 Software Programmig Iterfaces Etheret Iterface ad High Level Serial Iterface Iterface Files Iitial Coectio to the Commad Processor CHAPTER 6 ViVA Help Setup System Requiremets Istallatio...46 Versio...46 View Meu & User Iterface...46 Image Widow Types Image Layout Full Overlay...48 Status Bar Message Optio...48 Image Iformatio...50 Toolbars File Meu & Image Files...51 Savig Images Opeig Images Pixel Data Format & 3030CB / 4030CB Receptors...55 Edit Meu & Prefereces...56 iv

5 Edit Toolbars & Image Maipulatio...58 Cursor Fuctios Mouse ad Key Shortcuts Cotext Meus...59 Widow/Level Scroll Auto & Ivert W/L Edit W/L Dialog Acquisitio Meu/Toolbar...65 Commuicatio Lik Image Acquisitio...66 Offset & Gai Calibratio...67 Gai Ratio Calibratio Exteded Gai Calibratio...69 System Settigs...70 Mode Settigs...71 Rad AutoSave...73 Hardware Hadshakig Video Meu/Toolbar...74 Rad Modes Recordig Sequeces Playig Sequeces More Video Optios: Video Meu...76 Aalysis Meu: Image Statistics...79 ROI Basic...79 ROI Dialog RoiList Commads Tool Meu Receptor Commad Processor Defects...85 Image Operatios Coe Beam...95 CHAPTER 7 SYSTEM CONFIGURATION...97 Cofigure Utility Applicatio...97 Usage Mai Scree...99 Receptor Cofiguratio Settigs Mode Selectio Mode Setup System Cofiguratio: Hostdow Utility Applicatio System Cofiguratio: ViVA Applicatio CHAPTER 8 COMMAND PROCESSOR HARDWARE SPECIFICATIONS Hardware Compoets Commad Processor Hardware Cofiguratio Motherboard IPCU Exteral Sychroizatio: Hardware Hadshakig bit Video Output Sigals Logic Levels Frame Timig User Sychroizatio Mode Pulsed X-ray Beam Applicatios Timig Iformatio Iteral Power Supply Specificatios Cotrol ad Moitorig Mechaical Specificatios Commad Processor Specificatios v

6 CHAPTER 9 SAFETY Receptor Module Receptor Moutig Commad Processor Rack Moutig the Commad Processor Evirometal Coditios Coolig Requiremets Electro-Magetic Compatibility Electro-Magetic Iterferece Electrical Shock Protectio X-Ray Leakage with Pb Barrier Safety Agecy Approvals CHAPTER 10 MAINTENANCE Prevetative Maiteace Calibratio Schedule Receptor Module Repairs Cleaig, Disifectio ad Sterilizatio CHAPTER 11 TROUBLESHOOTING HyperTermial Problems ad Solutios CHAPTER 12 TECHNICAL SUPPORT How To Reach Us PaxSca 3030CB / 4030CB Problem Report vi

7 Figures PaxSca 3030CB / 4030CB Digital Imagig Subsystem PaxSca Imager Cofiguratio Iteral Cofiguratio of the Receptor Sesor Structure Offset ad Gai Correctio Algorithm...19 Commad Processor I/O...24 ViVA - Ope Etheret Lik ViVA - Fluoroscopic Acquisitio - Normal ViVA - Retrieve Image Selectig Fluoroscopic Mode Gai Calibratio...36 Gai Calibratio - Fluoroscopy Gai Fluoro - Frame Accumulatio Offset Calibratio: Dark Field Accumulatio Dark Field Accumulatio i Progress...38 Imager Aalyzig Fluoroscopic Gai Calibratio Complete Aalog Offset Settigs Aalog Offset Calibratio Progress Etheret ad High Level Serial Iterface Architecture ViVA Scree View...47 Message Optios Image Iformatio: Image Tab Image Iformatio: System Tab Image Iformatio: Video Tab File Format: Ay Specificatio Dialog Prefereces Dialog Box...56 Cotext Meu for Thumbview Cotext Meu for Imageview (Normal Mode) Cotext Meu for Imageview i Defect Map Editor Mode Edit Widow/Level Dialog...62 Gray Level Mappigs for Liear, PseudoFilm ad Ata/S-curve Fuctios Gamma Curve Adjustmet Dialog...64 Acquisitio Meu...65 Acquisitio Toolbar without lik ope Acquisitio Toolbar with lik ope Image Ifo: User Iput...66 Gai Calibratio Dialog...68 Acquisitio meu - dual read modes...68 Acquisitio meu - dyamic gai modes Exteded Gai Calibratio dialog System Settigs - No Lik Ope System Settigs - Lik Ope Mode Settigs - Fluoroscopy Modes Mode Settigs - Radiography Modes Video Toolbar Allocate Buffer Dialog Box vii

8 viii Video Meu Sequece Subset Ifo...76 Set AVI Quality Regio of Iterest Statistics Dialog Box Aalog Offset Settigs...83 Defect Map Editor Screeshot...86 Defect Threshold Tool Defect Map Coversio Warig...89 Fid Noisy Pixels Dialog Box...90 Image Arithmetic Dialog...92 Pixel Editor Dialog Optimize Auto Level Parameter Dialog...93 Extract from Image Iformatio Dialog...95 Usage Dialog Box...98 Mai Scree Dialog Box Ope Dialog Box...99 Receptor Cofiguratio Settigs DCDS Lie Legth Dialog Box Mode Selectio Dialog Box Mode Setup Dialog Box Hostdow Mai Scree Auto Dowload File Set ViVA Trasmit Files Selectio Commad Processor Hardware Itercoectio Geeric Opto-Coupler Iterface Frame Timig Vsyc Timig Diagram User Syc Fluoro Overall Timig Detailed View of Oe Hsyc ad Data Valid Full Resolutio Overall Video Timig with User Syc Full Resolutio Detailed Video Timig LVDS ad CameraLik Coector Pi Assigmets LVDS Sigal Termiatio Scheme Timig for Systems with Pulsed X-ray Beam Delivery Receptor Commad Processor HyperTermial Widow ViVA WIdow Com Port Cofiguratio

9 Tables Commad Processor Compoet Boards PaxSca 4030CB Stadard Modes...20 PaxSca 3030CB Stadard Modes...21 Cable Coectios Power O Sequece...27 Basic Offset Calibratio Gai Calibratio: All Modes Gai Calibratio: All Modes Aalog Gai Settigs - Target Values ad Tolerece Cursors Shortcut Key Combiatios Regio of Iterest Statistical Iformatio...81 Receptor Settigs Data Descriptio Mode Selectios System Cofiguratio Software Package Files Pi Assigmets of the Exteral Sychroizatio Port Default Hardware Hadshakig Iterface Default Hardware Hadshakig Sigals Video Iterface Sigals Typical LVDS Levels Recommeded LVDS Parts PixClk Timig Specificatios Vsyc/Hsyc/Data Valid Timig Specificatios Frame Rate vs. Vertical Blak Time Iteral Power Supply Specificatio Serial Port Oe (P1) Serial Port Two (P2) Etheret Coector (P3) Evirometal Coditios Troubleshootig ix

10 x

11 Chapter 1 Itroductio Figure 1-1 PaxSca 3030CB / 4030CB Digital Imagig Subsystem 1 Desiged ad maufactured by Varia Medical Systems, the PaxSca family of digital X-ray imagers uses amorphous silico flat pael detectors (FPDs) for X-ray imagig. They are desiged for icorporatio ito a complete X-ray system by a qualified equipmet maufacturer. The PaxSca 3030CB / 4030CB is the world s first 12 x16 multi-modality, digital X-ray flat pael imager for coe-beam medical imagig applicatios. It is available with a cesium iodide scitillator. Each PaxSca 3030CB / 4030CB system comes complete with Widows -based software for cotrol of operatig modes, real-time image acquisitio, correctio, trasfer, off-lie processig, ad display. PaxSca 3030CB / 4030CB imagers replace image itesifiers ad TV cameras i fluoroscopic X-ray applicatios. There are may possible readout modes sice the frame rate, sesitivity, field-of-view ad resolutio are all programmable. I a typical medical applicatio, the 3030CB / 4030CB would be cofigured to have multiple fluoroscopy modes. The PaxSca 3030CB / 4030CB has the ability to switch betwee multiple imagig modes i real-time. This maual describes the hardware, software ad mechaical iterfaces used i itegratig the PaxSca 3030CB / 4030CB imager ito a complete imagig system. Itroductio 1 11

12 1 12 PaxSca 3030CB / 4030CB Systems & Service Guide

13 Chapter 2 System Overview The PaxSca 3030CB / 4030CB is a real-time, fluoroscopic digital X-ray imagig subsystem icorporatig a large area amorphous silico TFT/photodiode sesor array with a cesium iodide scitillator. The PaxSca 3030CB / 4030CB will acquire images at usual video frame rates over a wide rage of dose. The 3030CB / 4030CB is desiged for diagostic X-ray tube eergies ragig from 40 kvp to 150 kvp. 2 Desiged as a subsystem, it caot be used as a stad-aloe device. It must be icorporated ito a complete X-ray system by a qualified equipmet maufacturer. I This Chapter Topic Page Receptor 2-15 Commad Processor 2-18 Iteral Power Supply 2-19 Modes of Operatio 2-20 Importat: The PaxSca 3030CB / 4030CB is desiged for maximum access to the patiet, with a miimum possible border o the active imagig area. No part of the PaxSca 3030CB / 4030CB is iteded to be attached to a patiet ad/or to cotact the patiet. The imagig system has three mai compoets. The Receptor, which houses the solid-state, flat pael sesor; the Commad Processor, ad the Power Supply. The Commad Processor is the iterface betwee the Receptor ad the imagig system. I medical applicatios, the fuctio of the Receptor is to absorb the X-rays that pass through the patiet s aatomy, ad to covert those X-rays ito a digital image. The Commad Processor ad Power Supply will typically be mouted i a equipmet eclosure ad will ot be i view or reach of the operator or patiet. The Receptor is mouted ito the OEM s moutig structure, such as a C-Arm, ad will ofte be completely covered by the moutig ad a cotrastehacig scree. Durig operatio, the C-Arm is ofte draped or bagged to esure clealiess ad sterilizatio, ad is maipulated such that the Receptor s iput widow is located ear, but o the opposite side of the patiet, from the X-ray source. Importat: It is possible that durig ormal usage the Receptor could iadvertetly cotact the patiet. The closeess of the Receptor to the patiet is depedet upo the operator ad the techique beig performed. 2 13

14 PaxSca imagers are iteded for cotiuous use. Figure 2-1 shows the cofiguratio of the Receptor i the cotext of the overall imagig system. The Receptor measures 18 x 14 x 1.6 iches. The receptor thickess icreases to 2.6 iches where the sap-o box is located. The Receptor ca be located up to 40 meters from the Commad Processor. A bi-directioal fiber-optic lik is used to pass all data ad mode cotrol sigals to the Receptor. The 24V/3A power for the Receptor is provided o a separate copper cable with quick discoect coectors. Figure 2-1 PaxSca Imager Cofiguratio The imager operatio is cotrolled usig software commads via Etheret, or oe of Serial ports. The set of possible imager cotrol operatios is supplied to systems itegrators i a C++ library of callable fuctios, i the form of a Wi32 DLL. The commuicatios iterface is at the level of IP sockets. Cotrol of the imager is platform-idepedet. The Commad Processor has a set of I/O sigals that ca be used for hardware hadshakig ad sychroizatio of critical tasks. The primary output of the Commad Processor is corrected 16-bit digital video or stadard camera lik video. Raw data from the Receptor are corrected for offset ad gai variatios o a pixel-by-pixel basis. The amorphous silico pael has a fiite umber of dead pixels ad lies, which are corrected i the Commad Processor through iterpolatio of the earest eighbors. The Commad Processor also provides a recursive filter to smooth frame-to-frame oise. The Power Supply provides all the DC power ecessary for both the Commad Processor ad the Receptor. The Power Supply coects to ay stadard wall outlet ad is coected to the Commad Processor through a 50-pi D sub-miiature coector. The Commad Processor ad Power Supply each have a footprit of 10.2 x 11 iches, ad whe stacked for rack moutig occupy a height of 5.2 iches PaxSca 3030CB / 4030CB Systems & Service Guide

15 Receptor The Receptor is based o amorphous silico (a-si) techology, which is very similar to that used i flat pael liquid crystal displays. Because X-rays caot be easily focused, it is a requiremet that the detector be as large as the area to be imaged. The PaxSca 3030CB / 4030CB a-si devices are fabricated oto a glass substrate i the same maer as TFTs i active matrix flat pael displays. The glass substrate is mouted o a base plate, which also holds the readout ad drive electroics for the Receptor. 2 I CCD-based systems, a large X-ray coversio scree emittig visible radiatio is coupled to the camera through a mirror ad les. The drawback to such a system is the substatial loss i sigal due to the relatively small solid agle i which light is collected. The larger the area to be imaged, the greater the loss Varia s amorphous silico paels allow optimal couplig betwee the X-ray coversio scree ad the photo-detector. Figure 2-2 Iteral Cofiguratio of the Receptor The core of the detector is a array of amorphous silico p-i- photodiodes ad thi film trasistors (TFTs), which are arraged as show below. Figure 2-3 Sesor Structure System Overview 2 15

16 O top of the amorphous silico (a-si) array is a X-ray scitillator, which coverts the X-ray photos to visible radiatio. This scitillator is typically a thallium-doped Cesium Iodide deposited directly o the a-si array. These X-ray coversio screes emit early 550 m, which correspods to the peak quatum efficiecy of the photodiodes. Amorphous Silico: Features ad Beefits Amorphous silico devices have bee show to be extremely radiatio hard. This feature makes a-si techology attractive for both diagostic eergy imagig (40 to 150 kvp) as well as mega voltage eergy imagig, such as might be doe i radiatio therapy ad high eergy o-destructive test (NDT) applicatios, where the dose rate from the source typically exceeds 100 cgy/mi. Amorphous silico devices have a umber of additioal features that make them well-suited to X-ray sesor applicatios: a-si ca be deposited over a large area oto glass substrates A low dark curret of the pi diodes Wide dyamic rage A low leakage curret of a-si TFT Capable of toleratig > 10,000 Gy (1Mrad) total dose i the active area. Ca image a wide rage of X-ray eergies i diagostic imagig ad o-destructive test (NDT) Very low pixel-to-pixel crosstalk A typical dark curret for the photodiodes is o the order of 2pA/mm 2. The OFF curret of a TFT is less tha 0.1pA for temperatures below 50 C. Such low dark currets equip the devices for use as charge itegratig detectors, allowig frame rates o the order of may secods per frame. The large itrisic dyamic rage of the amorphous silico pixel comes from the large charge capacity of the photodiodes. For a 194 µm pixel, the charge capacity is over 0.7 pf, which gives over 50 millio electros for a 5V reverse bias. Properties of Amorphous Silico The same lack of log-rage order i the amorphous silico (a-si) material that makes it radiatio hard, also meas that charge does ot move easily i amorphous silico. Sice the electro mobility i a-si is less tha 1 cm 2 /V sec, it is ot practical to build extesive readout electroics ito the a-si plate. As a cosequece, every row ad colum coectio must be brought out to the edge of the array where it is coected to covetioal itegrated circuits. This poses a umber of uique challeges whe compared to CCD or CMOS active pixel sesors where much of the sesitive readout electroics ca be built ito the detector PaxSca 3030CB / 4030CB Systems & Service Guide

17 The first challege is simply the mechaical coectio to the thousads of sigals, which come out to the edge of the array. The secod ad more difficult challege is that the architecture forces the readout circuit to operate i the presece of the large parasitic resistace ad capacitace of the a-si array. The domiat oise sources i the imager arise from these parasitics. I the same way that the a-si sesor techology is leveragig the huge ivestmet that has bee made i displays, the itercoect techology used i flat pael displays is also available for sesors. Typically, the row selectio ad readout electroics are put i TAB (tape automated bodig) packages. These flexible packages are heat sealed to a coductive ladig patter o the glass usig a z-axis coductig epoxy. The chip is mouted somewhere i the middle of the package. At the other ed of the package the sigal traces are either soldered or heat sealed to a prited circuit board. 2 The advatage of a TAB package over a simple flexible circuit itercoect, is the dramatic reductio i the umber of pis required at the PCB ed of the package. The readout chips are heat sealed at the glass to 128 colums, where the ladig patter has a pitch of 100 µm. The readout chip multiplexes these 128 iputs dow to oe output, so o the PCB ed of the package oly 30 pis at a pitch of 20 thousadths of a ich are ecessary to carry the power, cotrol sigals ad output sigal. Aother advatage of the TAB package is that the electroics ca be wrapped aroud to the side or the backside of the array, as show i Figure 2-2 for oe of the gate driver chips. The top ad bottom halves of the-si array are read i parallel, a sigle row at a time progressively. The parallel scaig feature of the 3030CB / 4030CB is eabled by the use of split datalies ad two sided readout electroics. This feature offers lower electroic oise, faster scaig ad a icreased time widow for pulsed X-ray beam delivery. Referrig to Figure 2-3, the gate driver chips select which row i the image is accessed, by applyig a positive voltage to a lie of TFT gates. With the TFTs ON, charge collected o idividual photodiodes i the selected row is the discharged oto the correspodig datalie. Each datalie is held at a costat potetial by a charge itegratig amplifier. I the PaxSca 3030CB / 4030CB, there are 1,536 rows ad 2,048 colums at a pixel pitch of 194 µm; therefore, 4,048 charge itegratig amplifiers o a effective pitch less tha 194 µm are required to readout the imager. A secod geeratio, custom 128-chael readout chip, the VENUS 4, has bee desiged i a BiCMOS process for this purpose. The VENUS chips capture the charge o each datalie, covertig the sigals to voltage levels, which are the multiplexed out to 14-bit aalog-to-digital coverters (ADCs). System Overview 2 17

18 To summarize the sigal coversio chai: X-rays are coverted to visible photos by the scitillator. The visible photos are absorbed by the pi photodiodes ad coverted to electro-hole pairs, which collect o the capacitace of the photodiodes. The pi photodiodes are discharged whe the pixel s TFT is tured ON. The charge is collected by a itegratig amplifier ad coverted to a voltage. The sigal voltage has a programmable gai applied, depedet upo operatig coditios. The output voltage is coverted to digital data by a ADC. Commad Processor The Commad Processor provides all hardware ad software iterfaces for the PaxSca 3030CB / 4030CB. It cosists of a embedded computer, image correctio hardware, ad exteral hardware iterface coectios. Table 2-1 Commad Processor Compoet Boards Compoet Board Descriptio CPU/Motherboard PM/PPC 440-based CPU board RJ-45 Etheret port Two serial ports System DRAM Flash memory Image Processor (IPCU) Hardware-based image correctio Offset/gai correctio Defective pixel correctio Correlated lie oise reductio Recursive filterig The software applicatio, Executive, ruig o the CPU/Motherboard iitializes all system compoets upo startup, hadles all software iterfaces (Etheret, Serial), ad iterprets sigals which arrive over the hardware iterfaces. The Executive also hadles frame-byframe cotrol of image acquisitio ad calibratio. Real-time correctio of images, o the other had, is provided by the IPCU. The Executive is a stad-aloe software applicatio, idepedet of ViVA. Figure 2-4 illustrates the iteral cofiguratio of the Commad Processor. The Commad Processor receives commads over the Serial or Etheret ports, cofigures the imager for the appropriate operatig mode, ad respods to hardware I/O sigals PaxSca 3030CB / 4030CB Systems & Service Guide

19 At the heart of the Commad Processor is a PowerPC 440GP CPU, which rus the VxWorks real-time operatig system (RTOS). Usig a RTOS allows the imager to respod to evets o a frame-by-frame basis. The Commad Processor cotais three baks of memory: DRAM associated with the PowerPC 440GP CPU High Speed Sychroous DDR (SDRAM), used i the image processig sectio No-volatile flash which stores the ru-time applicatio as well as the offset ad gai correctio values used o system start-up. 2 Offset ad Gai Variatios The image processig uit (IPU) corrects for offset ad gai variatios as well as defective pixels, o a pixel-by-pixel basis. Backgroud ad gai variatios are due to o-uiformity i the dark curret o the array as well as itrisic differeces betwee the readout amplifiers. Defective pixels origiate o the array. To correct for this pheomeo, the IPU uses data from the earest eighbors to estimate ad replace the defective pixel s value. The offset ad gai correctio algorithm ca be reduced to the followig formula: Figure 2-5 Offset ad Gai Correctio Algorithm The offset_data represet a image take with o illumiatio, i.e. a dark field. The gai_data represet a image take with o object i the X-ray path, i.e. a flat field, ad the gai_media is derived from the cetral part of the offset-corrected flat field. To miimize the error itroduced by the correctio data, the offset data ad gai data are determied by averagig up to 1,024 frames. For calibratio, two images must be collected: a dark field image ad a flat field image. This type of correctio has the added advatage of removig the spatial o-uiformity of the X-ray beam profile. It is expected that the frequecy of gai data recalibratio will be relatively low. Please refer to Chapter 4 for calibratio procedures. Iteral Power Supply The iteral power supply provides a 24V supply for the Receptor. Typically the curret draw is 3A o the 24V supply. The 3030CB / 4030CB Commad Processor has a user replaceable fuse o the power ilet WARNING: All regulatory approvals, icludig UL ad CE mark, are cotiget o the use of the Two- Output Power Supply provideded by Varia Medical Systems. If substitutios are made, these approvals are void ad the image quality caot be guarateed. System Overview 2 19

20 Modes of Operatio The PaxSca 3030CB / 4030CB supports a umber of modes of operatio, as defied i Table 2-2. Betwee each mode is a trade off of resolutio, or field of view, for frame rate, or oise. The sesitivity of the imager is optimized to match the X-ray dose used i each mode. The system may be i oly oe mode at a give momet. The operatioal states of the imager ca be categorized as follows: Offset calibratio: (OEM-iitiated, or hadled automatically by the software Executive) Gai calibratio: (always OEM-iitiated) Aalog offset calibratio: (always OEM-iitiated) Cotiuous acquisitio: (fluoroscopy-type) Each operatig mode employs all types of calibratio. The purpose of each mode is to cofigure the detector to achieve optimal performace durig specific imagig procedures. Modes are defied by a combiatio of factors, such as pixel biig, frame rates, aalog gai ad field-of-view. Each mode requires a uique set of calibratio data. Calibratio is discussed i more detail i Chapter 4. Not every mode will be available with every system. The OEM should work with PaxSca techical support for cofiguratio of the mode(s) which best suit the customer s iteded applicatio. All the modes show i Table 2-2 ad Table 2-3 are of the cotiuous acquisitio type, which employs accumulatio-type acquisitio. Mode Table CB Stadard Modes Max Frame Pixel Image Area Frame Size Active Gai/ Rate (Hz) Biig Frame Size Capacitor High-Sese Fluoro 30 2 x 2 Full Field 1,024 x x 758 4/0.5 pf Normal Fluoro 30 2 x 2 Full Field 1,024 x x 758 2/0.5 pf Full-Resolutio High-Sese x 1 Full Field 2,048 x ,028 x 1,516 2/0.5 pf Full-Resolutio High-Dose x 1 Full Field 2,048 x 1,536 2,028 x 1,516 2/4 pf Full-Resolutio 2 20 PaxSca 3030CB / 4030CB Systems & Service Guide

21 Table CB Stadard Modes Mode Max Frame Pixel Image Area Frame Size Active Gai/ Rate (Hz) Biig Frame Size Capacitor High-Sese Fluoro 30 2 x 2 Full Field 768 x x 758 4/0.5 pf Normal Fluoro 30 2 x 2 Full Field 768 x x 758 2/0.5 pf Full-Resolutio High-Sese x 1 Full Field 1,536 x ,516 x 1,516 2/0.5 pf Full-Resolutio High-Dose x 1 Full Field 1,536 x 1,536 1,516 x 1,516 2/4 pf Full-Resolutio 2 Default Mode The first imagig mode is the ormal default mode, although this ca be cofigured to meet the customer s specific applicatio requiremets. The default mode will be ivoked automatically uder the followig coditios: Upo system power-up Upo receipt of a reset state commad, via Etheret or Serial iterfaces Image Processig The Commad Processor performs offset ad gai correctio for each pixel. This elimiates fixed patter oise i the image ad makes dose respose of each pixel uiform. The Commad Processor also provides several other forms of image processig that are commoly required i fluoroscopy ad digital radiography. Coe-Beam imagig applicatios do ot support Offset, Gai ad defect correctios. For coe beam See Appedix C. Recursive Filter A temporal (recursive) filter is used to reduce oise i low dose fluoroscopic applicatios, at the expese of icreased image lag. The itrisic lag of the a-si pael is roughly 4% i the first frame, but ca remai at the 1% level for secods. The recursive filter combies a weighted average of the prior image frames with the curret iput frame. The recursive filter algorithm is: where α ca take o values betwee 0 ad Recursive filterig itroduces a cotrolled amout of lag ito the video output for the purpose of oise reductio. This is a commo techique i fluoroscopy, where the sigal levels are very low ad there is sigificat oise itroduced by the statistics of the X-ray beam itself. System Overview 2 21

22 Defective Pixel Replacemet The IPU uses earest eighbor averagig to replace defective pixels. This ca be doe successfully for sigle defective rows, for sigle ad double defective colums, ad for combiatios of a umber of defective sigle pixels. Saturatio Threshold The offset ad gai calibratio implemeted i the PaxSca 3030CB / 4030CB will fail oce the detector has reached saturatio, sice the respose to icreasig dose is ot liear. I images with large straightthrough radiatio, this ca lead to a stripe-like patter i the saturated regios of the image. This effect ca be miimized by a appropriate choice of gamma fuctio, or LUT, used for the display. Alteratively, the PaxSca 3030CB / 4030CB has a saturatio thresholdig fuctio at the iput of the image processig sectio. Pixels above a threshold value are set to a fixed, programmable value ad o correctios are applied. I some applicatios, the uatteuated dose to the Receptor pael ca far exceed the saturatio poit. I these situatios, a additioal image artifact may also be see. This image artifact is a level shift betwee the upper ad lower sectios of the image. The dose at which the artifact appears will deped o the beam eergy ad filtatio PaxSca 3030CB / 4030CB Systems & Service Guide

23 Chapter 3 Gettig Started This chapter describes the major compoets ad fuctios of the PaxSca 3030CB / 4030CB. The hardware iterface coectios ad a overview of the software used for image calibratio ad acquisitio is provided. I This Chapter Topic Page 3 Shipmet Cotets 3-23 Coectig the Cables 3-24 Mechaical Moutig 3-26 Power O Sequece 3-27 Establishig Coectio 3-28 Basic Offset Calibratio 3-28 Basic Gai Calibratio 3-29 Image Acquisitio 3-30 Shipmet Cotets Immediately upo receipt, ispect the shipmet ad its cotets agaist the Delivery Note eclosed with the shipmet for evidece of damage or missig compoets. Save all shippig cotaiers i case a retur is warrated. If there is ay discrepacy, please call the PaxSca Service Ceter at (800) , or (801)

24 Varia Part Number Compoet 18990/20786 PaxSca 3030CB / 4030CB Imager System with: CsI LN High Bright Receptor Fiber-optic Commad Processor with ABS (LVDS) meter (100 ft.) 24V Receptor power cable meter (100 ft.) fiber-optic data cable PaxSca 3030CB / 4030CB Systems & Service Guide USA style Mais power cable, 110 VAC Optios: RoadRuer R3-PCI-DIF Frame Grabber 7550 Digital Video Cable to R3 Board m Itegrated fiber ad 24V cable m Itegrated fiber ad 24V cable Lead cap/primary barrier m RJ45 to RJ45 Etheret crossover cable m Serial (straight type) 9-pi male-to-male cable m Serial (straight type) 9-pi male to female cable 660 Power cable mais, 220 VAC m Utermiated mais cable, 220 VAC m Exteral syc 50-pi MDR/D-Sub cable m Receptor grougig cable Coectig the Cables Figure 3-1 Commad Processor I/O 3 24 PaxSca 3030CB / 4030CB Systems & Service Guide

25 Step Table 3-1 Cable Coectios Actio 1. Coect the power cable from the Commad Processor power iput port to the wall outlet. 2. Coect the series fiber-optic cable from the commad processor to the receptor. 3. Coect the series 24V cable from the Receptor to the power supply. The fiber-optic cable coectors should be treated carefully. Do ot over-stress the strai relief sectio. Do ot exceed the 5 cm miimum bed radius for the fiber-optic cable Coect the Etheret cable from the Commad Processor Etheret port to a Etheret port o the host computer. If the Etheret coectio is poit-to-poit betwee oly the Commad Processor ad host computer, a RJ45 to RJ45 crossover cable must be used. This is shipped with the PaxSca 3030CB / 4030CB. 16-bit still images ca be captured by the Commad Processor ad trasferred to the host computer over this Etheret cable. 5. If available, coect a digital video data cable from the 16 bit digital video output to a image capture board i the host computer. 6. Coect either the camera lik cable or LVDS digital video cable depedig upo your applicatio from the Commad Processor to the host computer. 7. Coect the serial cable from the host computer s COM 1 port to the Commad Processor serial 1 port. The serial cable must be the straight-through type, ot the crossover type typically used betwee computers. The serial coectio is used for diagostics ad loadig ew software ito the Commad Processor. This coectio is ofte used durig ormal operatio to moitor commuicatios betwee the Commad Processor ad the host computer. Gettig Started 3 25

26 Mechaical Moutig WARNING: If the PaxSca 3030CB / 4030CB Receptor is to be used as a primary barrier to X-rays, the X-rays must impige oly o the etrace widow of the Receptor. The PaxSca 3030CB/ 4030CB Receptor lead cap will ot stop X-rays that do ot hit the etrace widow of the Receptor. WARNING: The equipmet is ot suitable for use i the presece of a flammable aaesthetic mixture with air, oxyge or itrous oxide. Receptor Moutig The Receptor should be mouted oto other pieces of equipmet usig the holes provided. The Receptor has a optioal lead cap which ca be used as a primary barrier to X-rays. As oted above, this barrier is oly effective if the X-ray beam is collimated i such a way that X-rays impige o the active surface of the Receptor. See Figure 8-14 for more iformatio Importat: The temperature at the back surface of the Receptor should ot exceed 35ºC whe the uit is istalled. This may ecessitate air flow over the back surface of the Receptor. Humidity levels should be betwee 10-90%, with higher limits for storage. WARNING: The Receptor is ot sealed agaist drippig moisture. Commad Processor The Commad Processor ca be rack mouted i a stadard 3U (5.2 high) slot usig optioal rack moutig iteded for a 19 wide rack. See Figure 8-15 ad 8-16 for more iformatio. Importat: The followig precautios should be observed whe rack moutig the Commad Processor: Elevated operatig ambiet temperature: If istalled i a closed or multi-uit rack assembly, the operatig ambiet temperature of the rack eviromet may be greater tha room ambiet. Equipmet should be istalled i a eviromet compatible with the maximum rated ambiet temperature. Reduced air flow: Istall the equipmet so that the amout of air flow required for safe operatio is ot compromised. Coolig air clearace is 10 cm (4 iches) miimum from each surface PaxSca 3030CB / 4030CB Systems & Service Guide

27 Mechaical loadig: The equipmet should be loaded evely ito the rack to avoid ay hazardous coditios. Circuit overload: Cosideratio should be give to the coectio to avoid overloadig of circuits o the over-curret protectio ad supply wirig. Reliable Groudig: Reliable groudig should be maitaied. Particular attetio should be give to the supply coectio, other tha the direct coectio to the brach circuit. The use of surge protectors are advised. Power O Sequece 3 The PaxSca 3030CB / 4030CB requires o actio or itervetio from the operator or the host system after power o, or before power off. The PaxSca will be fully operatioal ad ready to receive a Start Acquirig Image sigal or commad data withi approximately three miutes after power o. Actual startup time depeds o the umber of modes loaded ad the system cofiguratio. Whe startup is complete ad if the system is cofigured accordigly, a default mode test patter will be set to the video outputs. Full specificatio is achieved withi two hours after power up. The PaxSca 3030CB / 4030CB does ot require ay special warigs prior to power dow. No loss of data or setup iformatio will result from uexpected shutdow. Step Table 3-2 Power O Sequece Actio 1. Tur o the host computer ad allow it to boot up ad logi. 2. Tur o the Commad Processor. The Commad Processor must boot up before coectio to the viewig applicatio ca occur. A successful boot up ca be idetified i oe of four ways: 1. The LEDs Power, Frame, ad Ru are illumiated o the frot pael of the Commad Processor. 2. The default set-up is to display a test patter out the digital video port of the Commad Processor, if coected to a digital system. 3. The IP address is displayed over the serial port. 4. Pael_Ready becomes asserted o Hard Hadshakig Port. Oce ay of the four idicators are received, the Receptor is ready to acquire or view images. Gettig Started 3 27

28 Establishig Coectio ViVA is the viewig applicatio used to cotrol the Commad Processor. Varia Image Viewig ad Acquisitio (ViVA) is a o-commercial GUI program for cotrollig the PaxSca 3030CB / 4030CB "out of the box." It curretly rus oly uder Widows ViVA seds cotrol commads to the Commad Processor over a 10BaseT Etheret coectio. Some of ViVA s fuctios iclude acquirig images from the Receptor, viewig images, ad savig images to the hard disk. ViVA may also be used with a serial iterface, but ot for retrievig images. I order for ViVA to establish a Etheret coectio with the Commad Processor, the cliet IP address ad server IP address parameters must be cofigured. If your system cofiguratio has ot bee factory-set, please see Appedix B, Commad Processor ad Computer Iterface, to cofigure your system. For additioal assistace operatig ViVA, use the ViVA Olie Help file, or see Operatio, Chapter 6 of this guide. Basic Offset Calibratio Prior to acquirig images, a offset calibratio must be performed for each mode you ited to use. After the pael has bee powered up for thirty miutes, calibratio should be performed every te miutes, ad as eeded for clea images thereafter. A offset calibratio should be performed ay time the pael is iactive for more tha five miutes, or if the image seems to be degraded. Stadard calibratio defaults: Durig idle periods of operatio, auto offset calibratio will occur every five miutes. Post-exposure offset is every two miutes. Durig cotiuous operatio, a offset should be performed every five to thirty miutes, depedig o image quality ad applicatio time costraits. Coe-Beam modes ot supported. For coe beam See Appedix C PaxSca 3030CB / 4030CB Systems & Service Guide

29 Step Actio Results 1. Start Ivoke ViVA. Table 3-3 Basic Offset Calibratio 2. Ope Lik Select Etheret or Serial Coectio from the Acquisitio Mode dropdow meu. 3. Select Mode Select the desired mode from the Acquisitio Mode drop-dow meu. 4. Begi Offset Click Offset Calibratio butto, or select offset calibratio from the acquisitio pull dow meu. With ay calibratio selectio, a Accumulatig Dark Frames widow appears Acquire Images Click o Acquire Image to begi acquisio. Figure 3-2 ViVA - Ope Etheret Lik Basic Gai Calibratio The geeral procedure for Gai calibratio for all modes, is as follows, detailed istructios o performig gai calibratios are covered i Chapter 4. Coe-Beam modes ot supported. For coe beam See Appedix C. Gettig Started 3 29

30 Step Actio Results Table 3-4 Gai Calibratio: All Modes 1. Warm Up To esure proper warm up, the PaxSca 3030CB / 4030CB Receptor must be operatioal for at least two hours prior to Gai calibratio. 2. Radiatio A uiform flat field with o object i the path of the X-ray beam. The radiatio must be at a level ad techique represetative of the typical radiatio dose for the Receptor durig typical procedures. The exact level of the radiatio durig calibratio will ot ifluece the calibratio as log as the sigal level is ot saturated. 3. Offset Software automatically performs a ew Offset Calibratio calibratio followig the acquisitio of the flat field image. X-rays must be disabled. 4. Repeat The above procedure must be repeated for each of the stored modes. Image Acquisitio Oce Offset ad Gai Calibratio is performed, you are ready to acquire images. Fluoroscopy - Normal To acquire a image, click Acquire Image. The followig widow will appear: Figure 3-3 ViVA-Fluoroscopic Acquistio - Normal 3 30 PaxSca 3030CB / 4030CB Systems & Service Guide

31 This widow idicates that the Receptor is actively acquirig live images. Click Stop. The last frame or accumulated frames will be captured ad stored i the Commad Processor memory. To retrieve the last image stored i the Commad Processor to ViVA, click Retrieve Image. This will grab a image out of the Commad Processor memory ad trasfer it to the host computer. The thumbail image will be displayed i ViVA s image gallery. The image ca ow be viewed by draggig it ito the mai widow, ad/or saved to disk. Figure 3-4 ViVA-Retrieve Image 3 Gettig Started 3 31

32 3 32 PaxSca 3030CB / 4030CB Systems & Service Guide

33 Chapter 4 Calibratio Procedures The IPU i the Commad Processor FPGA corrects for Gai, Offset ad Aalog variatios betwee idividual pixels as well as globally across the image. This o-uiformity compesatio requires that a Gai referece image ad a Offset referece image be residet i the Commad Processor s high speed SDRAM memory prior to imagig procedures. Coe-Beam modes do ot support Offset, Gai ad Defect Correctios. For coe beam See Appedix C. 4 I This Chapter Topic Page Offset Calibratio 4-34 Gai Calibratio 4-34 Fluoroscopic Mode Gai Calibratio 4-36 Defective Pixel Maps 4-40 Aalog Offset Calibratio 4-40 Refereces to the OEM computer is as Cliet, while the PaxSca 3030CB / 4030CB Commad Processor is referred to as the Server. After Gai calibratio is complete, a Offset calibratio automatically follows. The Commad Processor will ot apply the Offset ad Gai correctio to pixels idetified as beig saturated. This feature of the o-uiformity correctio avoids iverse compesatio artifacts i regios where the image is saturated ad where o-uiformities are o loger preset. Offset calibratio compesates for fixed patter pixel itesity variatios i the image, associated with the dark curret (Receptor) ad electroic offsets itroduced by the readout ASIC ad the Aalog Board. The Offset referece image is a average of a series of frames acquired with o illumiatio, referred to as dark fields. The Gai referece image is a average of a series of frames acquired with uiform X-ray illumiatio, referred to as flat fields, across the active area. 4 33

34 The larger the umber of frames used i creatig the Gai ad Offset referece images, the lower the amout of oise cotributed to the image by the o-uiformity correctio. The Aalog offset calibratio reduces DC offsets created by variatios i electroic compoets, providig more dyamic rage. It is possible to dowload the Offset ad Gai referece images to the Commad Processor (Server) via the Etheret iterface. The curret Offset ad Gai referece images ca also be uploaded to the Cliet computer, via the Etheret iterface. Offset Calibratio The request to perform Offset calibratio ca be iitiated by the cliet system, via a software commad across the Etheret iterface, or the Commad Processor ca hadle the calibratio procedure autoomously. It performs all calculatios of correctio factors iterally ad stores the relevat data i memory, without requirig actio from the mai system or the operator. Some importat poits cocerig Offset correctio: Offset calibratio should ot occur while the X-ray is activated. The X-ray-to-digital coversio factor does ot chage as a result of calibratio. A differet offset referece image is ecessary for each operatig mode, therefore it is importat to update the offset data for each of the operatig modes. If the Prepare sigal o the Commad Processor s exteral sychroizatio port is asserted, the PaxSca 3030CB / 4030CB is able to abado a ogoig offset calibratio with o loss i precalibratio image quality. After abadoig a offset calibratio, the PaxSca 3030CB / 4030CB will be ready to acquire images withi four frames. The ready to acquire coditio is commuicated via the PaelReady sigal o the sychroizatio iterface. It is recommeded that a delay of at least 20 secods be allowed after a X-ray exposure, before commecig with offset calibratio. Sice there is some iheret lag i the detector, this delay avoids itroductio of a latet image ito the offset referece image. Importat: Sice the offset characteristics of the detector vary durig ormal operatio, the offset referece image must be updated at least every two to five miutes while the PaxSca 3030CB / 4030CB is warmig up, ad at least every 15 miutes oce it has reached its steady state temperature, typically after about two hours of operatio. Gai Calibratio To compesate for o-uiformities i the Receptor, a gai referece image (flat field) is used by the Image Processig Uit as required to correct all images i real-time. This flat field image must be captured by the Commad Processor prior to acquirig images, ad stored i o-volatile memory. The process of capturig the flat field image is kow as Gai calibratio PaxSca 3030CB / 4030CB Systems & Service Guide

35 Gai calibratio should take place at regular itervals, typically oce every three moths, or wheever the X-ray source has bee moved relative to the Receptor. Gai calibratio is based upo the liear respose of the Receptor to dose. Normalizatio is achieved by applyig the flat field image acquired i the Gai calibratio to all images passig through the Image Processig Uit. Normalizatio will fail with pixels that are respodig to dose i a o-liear maer. Pixels respodig to dose i a o-liear maer are usually caused by the saturatio of the Receptor, or a low sigal-to-oise ratio. These o-liear pixels will be marked defective durig the maufacturig process ad will be corrected by the Image Processig Uit. It is critical that the flat field image be acquired withi a rage that is large eough to be higher tha backgroud oise created by the X-ray source ad readout electroics of the Receptor, but lower tha the saturatio poit of the Receptor. 4 Flat field images acquired ear or exceedig the saturatio poit will cause ormalizatio failures with all images acquired util a Gai calibratio with the correct dose is performed. Varia recommeds that flat field images be acquired with a media cout of /-500. This rage will esure that Gai calibratio will meet both the upper ad lower dose requiremets uder all modes of operatio. To reduce the effects of oise, the average of each pixel i the flat field image is calculated by accumulatig a umber of frames ito a iteral buffer, the dividig the sum of each pixel by the umber of frames acquired. The larger the umber of calibratio frames used to capture the flat field image, the more precise the calibratio will be. The umber of calibratio frames used durig Gai ad Offset calibratios ca be adjusted uder the Mode Settigs pull dow meu. For more detailed iformatio, refer to ViVA i the Operatios sectio of this Guide. Varia recommeds accumulatig 128 frames i fluoroscopic modes, ad 32 frames i full-resolutio modes. For low frame rates, such as oe frame per secod, this may be too log a period. I such cases, it may be ecessary to lower the umber of calibratio frames to a more tolerable time period, ot goig below eight frames. After completio of the calibratio procedure, the followig iformatio will be viewable with ViVA via the Etheret iterface, upo request from the cliet: The media pixel value of the Gai image Gai ad Offset referece images The defect map image The media pixel value of the Dark Field image. Always use pulsed. Calibratio Procedures 4 35

36 Importat: The PaxSca 3030CB / 4030CB imagig system requires a warm-up of two hours prior to Gai calibratio. The geeral procedure for Gai calibratio for all modes, is as follows: Table 4-1 Gai Calibratio: All Modes Step Actio Results 1. Warm Up To esure proper warm up, the PaxSca 3030CB / 4030CB Receptor must be operatioal for at least two hours prior to Gai calibratio. 2. Radiatio A uiform flat field with o object i the path of the X-ray beam. The radiatio should be at a level techique ad filtratio represetative of the typical radiatio dose for the Receptor durig typical procedures. The exact level of the radiatio durig calibratio will ot ifluece the calibratio as log as the sigal level is ot saturated. 3. Offset Software automatically performs a ew Offset calibratio followig the Calibratio acquisitio of the Flat Field image. X-rays must be disabled. 4. Repeat The above procedure must be repeated for each of the stored modes. Fluoroscopic Mode Gai Calibratio 1. Select Acquisitio > Gai Calibratio from the ViVA meu bar. Figure 4-1 Selectig Fluoroscopic Mode Gai Calibratio 4 36 PaxSca 3030CB / 4030CB Systems & Service Guide

37 The followig widow appears: Figure 4-2 Gai Calibratio - Fluoroscopy 4 The imager will ow begi acquirig Flat Field images. Progress of the accumulatio ca be see i the followig figures. Follow istructios i the dialog box. Figure 4-3 Gai Fluoro - Frame Accumulatio 2. After the umber of acquired frames equals the umber of calibratio frames selected, the imager will be ready to collect Dark Field images. Follow istructios i the ew dialog box: Calibratio Procedures 4 37

38 3. The system will pause to allow lag to decay prior to performig a Offset calibratio. The followig widow appears: Figure 4-4 Offset Calibratio: Dark Field Accumulatio 4. As dark field accumulatio progresses, the followig widow is displayed: Figure 4-5 Dark Field Accumulatio i Progress 4 38 PaxSca 3030CB / 4030CB Systems & Service Guide

39 5. After acquirig the specified amout of dark images, the followig widow will appear idicatig that the imager is ow calculatig the gai data. Figure 4-6 Imager Aalyzig 4 6. Whe Gai Calibratio has completed the followig widow will be displayed with the Gai Calibratio statistics updated. Figure 4-7 Fluoroscopic Gai Calibratio Complete Gai media cout should be betwee / If the media value is higher tha 4,000, the dose used eeds to be decreased ad the gai calibratio repeated. If the media value is lower tha 2000, the dose eeds to be icreased, ad the gai calibratio repeated. Calibratio Procedures 4 39

40 Defective Pixel Maps The defective pixel map is determied durig Gai calibratio, usig iformatio from both the Offset ad Gai referece images. The map of defects is stored i the Commad Processor s iteral log term (flash) memory. Usig the defect map, the pixel correctio algorithm uses earest eighbor averagig to replace all defects i each video frame. Importat: Poits of ote about defect correctio: The pixel defect map is the combiatio of two defect maps: The first map, base, is determied at the factory ad does ot ormally chage. The secod defect map, aux, is ewly determied durig each Gai calibratio. Both types of maps are bit-wise ORed, the supplied to the image correctio algorithm. After correctio, o defective pixels should be visible i Flat Field images. It is possible to upload both defect maps from the PaxSca 3030CB / 4030CB to the cliet computer, via the Etheret iterface. It is also possible to replace the base map, residet i the Commad Processor, with a map dowloaded from the cliet computer, via the Etheret iterface. Aalog Offset Calibratio Aalog Offset calibratios are determied durig imagig system cofiguratio at the factory, or if a ew mode cofiguratio file is loaded. Aalog Offset calibratio reduces o-uiform pixel offsets created by differeces i the readout compoets located i the Receptor. By reducig the o-uiformity i the Receptor electroics, the overall dyamic rage of the system ca be optimized. To iitiate a Aalog Offset calibratio, the cliet computer must sed a software commad, via the Etheret iterface or Serial iterface, to the Commad Processor. The Commad Processor will the iitiate the Aalog Offset, perform all ecessary calculatios, ad store resultig offsets i o-volatile memory. 1. Select Aalog Offset Calibratio from the Tools->Receptor pull dow meu ad the followig widow will appear PaxSca 3030CB / 4030CB Systems & Service Guide

41 Figure 4-8 Aalog Offset Settigs 4 Aalog Offset Calibratio is ot available for Coe-Beam modes. For coe beam See Appedix C. 2. Set Target Value ad Tolerace based o Aalog Gai Settig (see table below). Table 4-2 Aalog Offset Settigs - Target Values & Tolerece Aalog Gai Target Value Tolerace Press Calibrate ad the system will begi the calibratio progress. ViVA will report the progress of the calibratio by idicatig the umber of Iteratios completed. Figure 4-9 Aalog Offset Calibratio Progress Oce that target value has bee reached the calibratio will complete ad the followig widow will appear promptig you if you like to perform a Gai Calibratio. After each Aalog Offset Calibratio the mode must have the Gai Calibratio performed agai. If Yes is selected the system will lauch the gai calibratio process. If No is selected the aalog offset calibratio will be exited. Calibratio Procedures 4 41

42 Verificatio of Aalog Offset Calibratio 1. Disable all image correctios via Acquisitio->System Settigs. 2. Acquire image. 3. Retrieve image. 4. Click Edit W/L butto. 5. From Edit Values sectio, select Bottom\Top. 6. Set Top field based o the Aalog Gai settig of the mode. If Aalog Gai is set to 1, the set Top Field to 751 ad Bottom Field to 750. If Aalog Gai is set to 2, the set Top Field to 1001 ad Bottom Field to If Aalog Gai is set to 4, the set Top Field to 1001 ad Bottom Field to To get aalog gai settig select Acquisitio->Mode Settigs. 7. Image should appear all white, with the exceptio of defects. 8. If step 7 fails, repeat aalog offset calibratio procedure. Importat: Aalog Offset calibratio requires o X-rays durig the calibratio procedure. It is recommeded that the system be powered O for at least two hours prior to performig a Aalog Offset calibratio. A differet Aalog Offset calibratio is required for each mode. It is recommeded that a delay of 60 secods be allowed after a X-ray exposure, before performig a Aalog Offset calibratio. A Offset ad Gai calibratio must be performed after completig the Aalog Offset calibratio. The Receptor cofiguratio file will be modified i the Commad Processor. This ew file should be uploaded to the Cliet computer. Verify Aalog Offset calibratio PaxSca 3030CB / 4030CB Systems & Service Guide

43 Chapter 5 PaxSca Applicatio Software I This Chapter Topic Page Software Programmig Iterfaces 5-43 Software Programmig Iterfaces There are three iterfaces which ca be used to cotrol the PaxSca 3030CB / 4030CB imagig system. Each are icluded i the CD-ROM provided with each system. They are: Etheret Iterface: A sockets -based iterface which provides full access to PaxSca 3030CB / 4030CB fuctios. The Widows side of the iterface is implemeted as a Wi32 DLL. The programmer does ot eed to do ay sockets programmig, but ca simply make sychroous fuctio calls to the DLL. High Level Serial Iterface: Provides all the same fuctios as the Etheret Iterface, with the exceptio of four fuctios which implemet uploadig ad dowloadig of image ad cofiguratio files. It also uses exactly the same Wi32 DLL as the Etheret Iterface. This serial iterface is implemeted o top of the AIA Stadard Serial Iterface outlied below. 5 AIA Stadard Serial Iterface: Provides good fuctioality, but with the added resposibility for the programmer to completely implemet oe side of the iterface. The commads themselves are character-based, ad are sufficietly simple that they ca be used to cotrol the PaxSca 3030CB / 4030CB from a ASCII termial, or termial emulator program. Devices with limited computig power might choose to use this iterface. This sectio provides a geeral overview. Each of these are explaied more fully o the CD-ROM provided with your system, or i the PaxSca Commuicatios Maual. Etheret Iterface ad High Level Serial Iterface These two iterfaces will be treated together, because from the programmer s perspective, they are implemeted i a idetical fashio. Figure 5-1 shows the architecture of a system usig these iterfaces. Figure 5-1 Etheret ad High Level Serial Iterface Architecture Widows XP PC 5 43

44 Although the DLL provides both Etheret ad Serial coectivity, oly oe iterface may be used at a give momet. The implemetatio of the iterface esures that all commads are executed sychroously. Oly oe commad is active at a time. This helps make the system more robust ad efficiet. It also provides a fuctio call paradigm, ot a message-passig oe, for the programmer. Iterface Files Three files are provided to the customer for implemetatio of each iterface: vip_comm.lib: a library file that should be icluded i the project if the programmer is usig the Microsoft Visual C++ eviromet. vip_comm.h: a C-style iclude file which has bee used successfully i differet build eviromets. vip_comm.dll: allows the programmer to create a library file i other developmet eviromets. All fuctios have a it retur type, represetig the success or failure of the call, with a o-zero value idicatig a error coditio. Defiitios of errors ad other required costats are give i the PaxSca Commuicatios Maual. To avoid amespace coflicts, the ame of each fuctio begis with vip_, ad the ame of each costat with VIP_. Iitial Coectio to the Commad Processor The programmer iitiates a coectio to the Commad Processor by followig these steps: 1. Type vip_ope_lik( ). This coectio type, Etheret or Serial, is idicated i the first call. 2. A coectio is termiated by callig vip_close_lik( ). Other commads, as defied i the PaxSca Commuicatios Maual, ca be used to istruct the PaxSca 3030CB / 4030CB to perform a wide variety of operatios. A example of the most commoly used commads ca be viewed i the Software Iterface Code sectio of the PaxSca Commuicatios Maual. This sample code is also available i the Vip_Comm directory of the PaxSca Software release folder. More complete examples of how the iterface fuctios are used are outlied i the PaxSca Commuicatios Maual PaxSca 3030CB / 4030CB Systems & Service Guide

45 Chapter 6 ViVA Help The ViVA software applicatio is a Widows-based program desiged to be used with PaxSca products to perform basic tasks. ViVA ca be used to cotrol axquisitios with PaxSca products ad also display ad maipulate images o a Widows PC that is ot coected to a PaxSca system. ViVA targets medical images as exclusively displays 16-bit image formats. This ViVA Help documetatio is desiged to assist users with use of the ViVA. I This Help Documet Topic Page Setup 6-46 View Meu & User Iterface 6-46 File Meus & Image Files Edit Meu & Prefereces 6-56 Edit Toolbar & Image Maipulatio 6-58 Acquisitio Meu/Toolbar 6-65 Video Meu/Toolbar 6-74 Aalysis Meu: Image Statistics 6-78 Tools Meu 6-82 I this sectio primary ViVA commads from meus or toolbars are i bold type. For icreased clarity i places a meu ad meu item may be specified with a vertical separator (e.g. File Close). Commads ad cotrols foud i dialog boxes are geerally i bold italic type. Refereces to sectios of this chapter are i bold uderlie. ViVA uses a umber of commo terms ad otatios that have special meaigs: Meu items edig with three periods (e.g. File Ope...) idicate that executig the commads will require further iput from the user i a dialog box. Meu items without the periods ormally require o further ivolvemet by the user ad will be executed immediately. I a dialog box, a Cacel butto implies closure of the dialog box without executig data o the dialog box. The Apply butto implies executio of data o the dialog box that updates data ad/or the Commad Processor. The OK butto performs the same tasks as the Apply butto if they have ot bee executed, the closes the dialog box. 6 45

46 Setup System Requiremets ViVA will ru o Itel-based PCs usig Widows XP. Geerally, acceptable performace i image viewig ad maipulatio ca be obtaied with ay Petium CPU system. The umber of ope images is limited by the combiatio of physical ad virtual memory. The quality of the video card, hardware, firmware, ad driver software also impacts the perceived speed of operatio. Whe used with a frame grabber card, system requiremets are more demadig; the followig is provided for guidace. A miimum system specificatio icludes a Petium III processor ruig at 1GHz or better with at least 512MB RAM ad preferably 1GB. It is also strogly suggested that you check the frame grabber maufacturer s recommedatios regardig specific hardware. The iteded use of the system may dictate larger amouts of RAM sice capturig video sequeces geerally requires at least eough memory to store the largest expected sequece + a additioal 128MB. Istallatio The Setup.exe i the root directory of the PaxSca CD provides a automated istallatio process for ViVA ad ay depedet files. Setup.exe is automatically started whe the CD is iserted ito a CD drive uless the Auto-Ru CD optio is tured off. To start Setup.exe maually, use the Ru commad uder the Widows Start butto to execute X:/Setup.exe, where X is the drive letter of the CD drive that cotais the PaxSca CD. Setup.exe will create a shortcut of ViVA o the desktop. To uistall ViVA, ru the Add/Remove applicatio i the Cotrol Pael ad remove the etry PaxSca. Ruig this automatic uistall program will also remove all other PaxSca compoets such as Commad Processor files ad Hostdow files that were previously istalled oto the hard drive. To ru ViVA, locate ad double click the shortcut of ViVA o the desktop. Versio ViVA versio iformatio is available from the Help About ViVA... commad. This dialog will also show iformatio about ay dlls i use. If a lik to a Commad Processor(CP) is ope, the dialog will also allow iformatio o the CP software ad firmware versios to be obtaied. View Meu & User Iterface Various commads described below allow customizatio of the image ad toolbar layout. These settigs are stored i the viva.ii file whe the program exits ad ViVA will lauch with the same prefereces selected whe ext used. The viva.ii file is automatically created with default settigs by ViVA whe it lauches if oe exists already PaxSca 3030CB / 4030CB Systems & Service Guide

47 Image Widow Types ViVA does ot use the stadard Widows MDI (Multiple Documet Iterface) arragemet of multiple, overlappig, moveable ad resizable widows. Istead, the applicatio offers two other types of widows for displayig images: a scrollig image gallery, Thumbail View or Thumbview, ad fixed frame Imageview widows. A scree shot of the ViVA user iterface is show i figure 1. Figure 6-1 ViVA Scree View 6 Most image maipulatio operatios ca oly be performed o a Imageview ad ot o a Thumbview. I additio to the image file ame, the Imageview widow also displays iformatio about magificatio (zoom), widow/levelig, image size, ad, for the pixel uder the mouse cursor, (x, y, value) data. The size of the Imageview widows is adjusted automatically to fit the size of the mai widow of the applicatio. The arragemet ad umber of widows ca be selected usig the View meu. Newly opeed or acquired images appear i miiature i a ThumbView widow which holds all the active ad opeed images. Images retrieved from a receptor are also automatically displayed to a image pae. The Thumbview widow ca be positioed horizotally alog ay selectable from the View meu. Images ca be moved from the Thumbview by draggig ad droppig to oe of the larger Imageview widows. There may be up to 16 of these, ad the preferred laytout may be cofigured from the View meu. Whe a image is dragged from the Thumbview to oe or more Imageview widows, the separate views of the image are logically liked. Oly oe copy of the pixel data is stored i memory for use by all views of that image. ViVA Help 6 47

48 A Thumbview or Imageview ca be selected by clickig o the view with the mouse poiter. The curretly selected Imageview is ormally idicated with a bright gree selectio rectagle. Other liked views of the same image show i the selected view are idicated with a bright blue selectio rectagle. May meu items icludig File Close or File Save As... are applicable to the selected image. Image Layout Uder the View meu, there are a umber of optios cotrollig the layout: Thumbview Positio allows the user to place the Thumbview alog ay edge, while Show Thumbview allows it to be show or hidde. Sigle-Image Layout, Two-Across Layout ad Four-Image Layout allow the user to choose from amog commo formats. Number Images Across ad Number Images Dow allow greater flexibility i selectig other multi-image layouts. Show Border allows the user to hide or show certai borders that are ormally show. Image refers to the gree border aroud the image itself. Select refers to the colored border aroud the image pae (applies to Imageview oly). Pae refers to the Widows style settig that by default creates a bevelled look at the pae edge. Full Overlay Certai iformatio appears i the corers of each thumb or image pae. This is referred to as the overlay, ad the more detailed iformatio i the lower corers may be show or hidde usig the View Full Overlay commad. This ca be useful whe displayig a large umber of images. Status Bar The View Status Bar commad allows the user to display or hide the status bar o the bottom of the mai widow. The status bar displays a short descriptio of some pull-dow meu commads whe highlighted by the cursor. Alteratively, the status bar displays the curretly selected mode (Fluoroscopy, Radiography...) whe the cursor is placed i other sectios of the applicatio. Message Optios Message boxes are displayed durig ViVA operatio. These are ormally classified as oe of three types: Iformatio or Ifo the message box cotais iformatio that may be useful i the curret cotext. The title of the message box is ViVA Message Box. Data Loss Warig or DataLoss a warig that a operatio risks loss of data. For example if a attempt is made to close a image which has ot bee saved. The title of the message box is ViVA Message Box - Data Loss Warig PaxSca 3030CB / 4030CB Systems & Service Guide

49 Error A error has occurred which could be a system error or iteral ViVA error. This may result i a operatio beig aborted. The title of the message box is ViVA Message Box - Error. The message box style may allow the user to cotiue the operatio (OK butto) or cacel the operatio (Cacel butto). I some cases (Ifo or DataLoss) the message may also be posed as a questio with YES/NO buttos. I such cases the ico will be a questio mark. However, the message box classificatio remais as Ifo or DataLoss as idicated by the dialog title. Certai Ifo messages that are routiely displayed before completio of a commad allow the user to elect ot to display the same message agai. Oce this electio is made, the user preferece is stored i the viva.ii file ad remembered upo future ViVA lauches. The View Message Optios commad displays a dialog, show i figure 2, which permits a umber of modificatios as to which messages are displayed: SHOW all DotShowAgai Messages resets all messages back to o. KEEP Messages as they are ow is the default ad o chages are made. 6 HIDE Ifo Messages (util ViVA closes) hides all Ifo messages util ViVA closes oly. HIDE Warig/Ifo Messages (util ViVA closes) hides all DataLoss ad Ifo messages util ViVA closes oly. The lower two optios should ot ormally be selected but may be useful i certai situatios where some repetitive series of operatios is beig carried out. Figure 6-2 Message Optios ViVA Help 6 49

50 Image Iformatio Whe images are retrieved from the CP, a header cotaiig iformatio o curret settigs is automatically geerated. The View Image Iformatio commad displays the iformatio cotaied i this header i a series of tab-eabled dialog boxes which are illustrated i the followig figures: Figure 6-3 Image Iformatio: Image Tab Figure 6-4 Image Iformatio: System Tab 6 50 PaxSca 3030CB / 4030CB Systems & Service Guide

51 Figure 6-5 Image Iformatio: Video Tab This tab is abset if video is ot eabled. 6 Toolbars There are three basic toolbars used i ViVA. They are stadard Widows toolbars which may be docked to floatig, ad the cofiguratio i use whe ViVA closes is stored i the viva.ii file for the ext lauch. The Image Edit toolbar is orieted vertically ad may oly be docked alog the left or right edges of the mai ViVA widow; it defaults at the left. The Acquisitio toolbar is orieted horizotally, may be docked top or bottom ad by default docks alog the top edge of the mai ViVA widow. The Video toolbar maybe docked alog ay edge, defaultig to the right. I additio a Defect Map Editor toolbar replaces the Acquisitio toolbar whe the defect map editor is ope. File Meu & Image Files ViVA ca ope, close, save, copy ad prit images. This sectio describes these operatios. Savig Images Choosig File Save As... will display a stadard Widows file/save dialog box. The user ca choose to save a image i the formats discussed above i the supported file formats described below. ViVA Help 6 51

52 Savig Idividual Images The followig file formats are supported for savig idividual images: ViVA (.viv): ucompressed 16-bit usiged data together with a custom 2,048 byte header cotaiig both optioal user-etered iformatio as well as automatically retrieved settigs i effect at the time a image was obtaied. This is the default. Raw (.raw): ucompressed 16-bit usiged data are saved without ay header or other iformatio tha the pixel values. ViVA oly supports certai predefied image sizes for this format. Bitmap (.bmp): ucompressed 8-bit widow-leveled Widows bitmap. the image is saved usig the curretly applied widow/level ad gray-mappig. JPEG (.jpg): compressed 8-bit widow-leveled JPEG. The user is asked to supply a quality factor i the rage 1-10 where 10 gives the highest quality ad largest file size. The image is saved usig the curretly applied widow/level ad gray-mappig. Iteral Varia Format (.asi): ucompressed 16-bit usiged data together with a custom 512 byte header. Similar to the.viv header but provided primarily to allow images to be exported to other Varia products. Tiff 16-bit (.tif): ucompressed 16-bit usiged data which may be opeed by tiff readers that support 16-bit data. Note that ViVA, by default, scales the pixel values to utilize more fully the 16-bit rage. This geerally results i a more satisfactory experiece whe opeed by readers that do ot perform ay automated widow/levelig. This scalig may be tured off i the Prefereces dialog. Note that ViVA does ot support opeig tiff images i geeral, but will ope 16-bit tiff images it has saved, restorig the correct pixel scalig. Tiff images may be accessed from the ope file dialog usig the Ay Files filter or whe applicable the most recetly used files uder the File meu. For the special 2MSBs are expoet pixel data format (see Pixel Data Format & 3030CB / 4030CB Receptors), a warig will be give that the image will first be coverted to a scaled image. Tiff 8-bit (.tif): ucompressed 8-bit usiged data which may be opeed by typical tiff readers. The image is saved usig the curretly applied widow/level ad gray-mappig. Savig Video Sequeces The followig file formats are supported for savig video sequeces: Video Sequece (.seq): ucompressed 16-bit usiged data together with the same 2048 byte header as the.viv format. AVI Sequece (.avi): compressed 8-bit widow-leveled AVI. As for.jpg a quality factor i rage 1-10 should be etered. Opeig Images Images ca be opeed for display ad maipulatio usig the meu optio File Ope... The opeed image will appear i the Thumb View; ad may be dragged to a Image View as required PaxSca 3030CB / 4030CB Systems & Service Guide

53 The opeed image is first displayed with a automatic widow-levelig settig which is iteded to show image features across a broad rage of cotrast. If a image is successfully opeed, the path ad file ame of the image is saved as the latest etry oto the most recetly used file list which ca be used as a shortcut to ope the file. ViVA supports opeig a umber of file formats, some of which have specific purposes, ad may ot be useful to most users. Except as ote oly formats havig 16-bit usiged data are supported geerally. File Ope... supports: ViVA (.viv): 16-bit usiged data with 2048 byte header. Raw (.raw): sice there is o header iformatio, oly particular predefied image sizes ca be opeed i.raw format. Img (.img): similar to.viv with 1024 byte header but oly image dimesioal data are read. Video Sequece (.seq): 16-bit usiged data with 2048 byte header. Differs from.viv oly by havig more tha oe frame. CT 16-bit siged (.slice): This data format is siged with o header. Oly the predefied image sizes used for the.raw format are supported. CT 16-bit usiged (.prj): 16-bit usiged data with 72 byte header. Image iformatio from the header is displayed as the image opes. HNB compressed 16-bit usiged (.hb): 16-bit usiged data i a compressed format. There is a 512 byte header, but oly image dimesioal data are read. HNC compressed 16-bit usiged (.hc): Similar to.hb. HND compressed 32-bit usiged (.hd): hd images are imported but it is assumed that oly 17 bits are used. As described i 3030CB / 4030CB extesios, ViVA supports a custom format desiged to allow iteger values up 17-bits to be hadled. Ay Files: (*.*): With limited scope, this allows geeric file types to be opeed for viewig; File Ope...permits opeig ay file which has ucompressed 16-bit usiged data residig i a cotiguous block (assumes Little Edia/Itel byte arragemet). Additioal iformatio may be preset provided its dispositio withi the file is kow. The user is asked for 3 fields of iformatio: header size, image width ad image height. These are automatically iitialized with best guess values based upo the predefied.raw image size which miimizes the header size. Whe the user chages oe of the image dimesio fields the other field is automatically adjusted the first time but ot subsequet times. This is to permit the possibility of trailig iformatio after the pixel block i the file. i.e. the header ad image dimesio fields are ot forced to defie the file size. Header ad trailer iformatio is igored ad caot be accessed by the Image Iformatio commad. The dialog box illustrated i the followig figure will be displayed whe opeig a file with Ay Files as the specified filter. 6 ViVA Help 6 53

54 Figure 6-6 File Format: Ay Specificatio Dialog Closig Images To close idividual images, select File Close. If close is selected for a Thumbview, that view ad ay associated image view widows will be closed as well. If a Imageview is selected whe Close is chose, oly that view of the image will be closed, leavig the Thumbview of the image ad ay other Image View widows ope. To close all curretly ope images, choose File Close All. This selectio will close all ope images i both the Thumbail View ad Image View widows. Please see Image Widow Types for a descriptio of widow types (Thumbail View ad Image View widows) ad Supported File Formats for supported image file types. Usaved images have a asterisk (*) appeded to the ame; if you attempt to close a usaved image, you will be prompted before closig it.. Savig as a 8-bit format does ot clear the asterisk (*). Pritig Images To prit a image, choose File Prit... which will prit the curretly selected image from either the Thumbview or the Imageview. Choose File Preview... to display a prit preview of a image. This selectio will provide a scree display of a prit copy of the curretly selected image from either the Thumbview or the Imageview. This optio is iteded to show the layout of a pritout for a image, ot the quality of the pritout. The priter setup ca be accessed through File Prit Setup... This selectio will allow the user to select priter ad paper optios PaxSca 3030CB / 4030CB Systems & Service Guide

55 Copyig Images Select Edit Copy to copy the image curretly selected oto the clipboard memory. This fuctio always copies the whole image usig the curret widow-level settigs, ot just the sectio of the image beig displayed i the Imageview. Pixel Data Format & 3030CB / 4030CB Receptors A Coe Beam Mode Type is displayed for 3030CB / 4030CB receptors (System tab, figure 4). This may be oe of: /a (i.e. a ormal mode with pixel data format 16-bit usiged), DUAL_READ or DYNAM- IC_GAIN. This iformatio field is stored i the viv header, ad refers to the origial mode type used to acquire the image. The curret pixel data format is listed i the System tab (see figure 4). Prior to the 3030CB / 4030CB receptor this has always bee Usiged 16-bit. Pixel iformatio is still stored as 16-bit values, but may ot be iterpreted ecessarily as simple usiged itegers. The 3030CB / 4030CB still provides 14- bit data, but it is capable of operatig i dual gai modes. I dyamic gai modes the 15 th bit specifies lo(0) or hi(1) gai. I additio sice the ratio of the gais ormally exceeds 4, the rage of values i a image caot be represeted as 16-bit itegers. A ew corrected pixel data format is used for 3030CB / 4030CB corrected images. 6 The pixel data format field which is stored i the.viv image header determies the pixel data format which may be oe of the followig: 16-bit usiged iteger ormal format for all receptors except 3030CB / 4030CB (specifically dual read or dyamic gai mode images). 2 MSBs are expoet the oly corrected format curretly supported for 3030CB / 4030CB. Here the 2 most sigificat bits are iterpreted as formig a expoet (value =0,1,2,3) for the other 14 bits. The pixel value is calculated as: pix = mat * 2^ where pix is the pixel value (0-131,064), mat is the 14-bit value formed by the 14 LSBs ad is the expoet formed by the 2 MSBs. CB raw DUAL_READ a raw ucorrected image obtaied usig a dual read mode where each pixel value is represeted twice for lo ad hi gais. CB raw DYNAMIC_GAIN a raw ucorrected image obtaied usig a dyamic gai mode where each pixel value is represeted oly oce ad the gai is determied from the 15 th bit as metioed above. Usgd 16-bit, Split Hi a raw ucorrected image obtaied usig a dual gai mode, but oly the hi gai pixel values are preset. Usgd 16-bit, Split Lo a raw ucorrected image obtaied usig a dual gai mode, but oly the lo gai pixel values are preset. ViVA Help 6 55

56 Displayig images i o-stadard formats Images i the 2MSBs format are displayed correctly by ViVA which iterprets the values as defied above. Other formats are displayed as if they are 16-bit usiged data format. This is actually oly wrog for the CB raw DYNAMIC_GAIN format, i which case those pixels obtaied i hi gai are displayed as the 14-bit value May ViVA arithmetic operatios are hadled correctly for these formats icludig the 2MSBs format, but NOT the CB raw DYNAMIC_GAIN. Whe operatios are ot available for a particular format the meu item is disabled (grayed). Edit Meu & Prefereces The Prefereces dialog ca be displayed via the Edit Prefereces. This dialog box, show i the followig figure, cotais certai settigs which are maitaied betwee differet lauches of ViVA. Figure 6-7 Prefereces Dialog Box These settigs are saved i the text file viva.ii, i the same directory as the applicatio executable viva.exe. The available settigs followig the groupigs i the dialog are as follows: Coectio Attributes The Host Computer ad Cmd Processor (Commad Processor) IP adddresses may be set. Some validity checks are doe o IP addresses. The previous seve IP addresses are kept i the list box for rapid reselectio. Coectio at Startup Depedig upog the selectio here, ViVA will attempt to automatically lik to the receptor at lauch PaxSca 3030CB / 4030CB Systems & Service Guide

57 Gray Levels User prefereces for the display of pixel values i fluoroscopy ad radiography modes. By default large pixel values are white i the image ad small values black. As referred to above uder Savig Images, pixel values are scaled by default whe savig as tiff images. This selectio allows the user to tur this feature off if required. White Area Blakig Activate ad select white area blakig threshold ad replacemet values. More iformatio is give o White Area Blakig i the descriptio of the Edit W/L dialog i the Edit Toolbar sectio below. Certai selectios such as White Area Blakig ad Widow/Level Mappig, appear to be duplicated i the Edit W/L dialog. The distictio is i applicability. Choices made i the Prefereces dialog apply to all images opeed subsequetly. Choices made i the Edit W/L dialog applies to the curretly selected image oly. 6 Widow/Level Mappig Here you may choose how the pixel values are mapped to gray levels i the display. Optios are Liear, PseudoFilm, No-Liear (A-ta / S-curve) or GammaCurve. Whe GammaCurve is selected the Set Gamma Curve Default butto is active ad allows you to customize the gamma curve as approximated by a multi-liear mappig fuctio. These settigs are saved ad used wheever a image is opeed from a file or retrieved from the CP. They are ot applied to ay images already ope. More iformatio is give o Widow/Level Mappig i the descriptio of the Edit W/L dialog i the Edit Toolbar sectio below. Save Betwee Sessios Certai settigs may be saved betwee sessios (ViVA lauches) icludig Mai Widow Size/Positio. If Use Saved System Settigs is checked, the optios such as Offset Correctios ad Gai Correctios will be set from from the settigs saved i the viva.ii file. If uchecked, existig system settigs i the Commad Processor will be used. The Recetly Used File List determies the maximum umber of file paths saved for rapid access from the File meu, ad may be set up to a limit of 16. The Thumbview Size i scree pixels may be adjusted. ViVA Help 6 57

58 The Pae Overfill Optio allows the user to specify how the magificatio is chose whe a image is first displayed i a image pae. By default this is set to 100% meaig that the whole image is always displayed ad the maximum magificatio is chose subject to thsis requiremet. Settig this value to a smaller % may result i a larger magificatio beig chose, at a cost of some portio of the image ot beig displayed. Edit Toolbar & Image Maipulatio The Image Edit (left-vertical) toolbar provides cotrols for cursor selectio, widow/level adjustmet as well as a butto for display of ROI statisitics. Cursor Fuctios This sectio describes the five-cursor types curretly implemeted i the ViVA Image Edit toolbar. For all the cursor types, the (x, y, value) for a pixel is displayed i the bottom corer of a Imageview widow. The image pixel correspods to the poit uder the active spot o the cursor. The differet cursor types are described i Table 1 below. Table 6-1 Cursors Click Result Stadard Selectio: Used for view selectio (click o the view) ad for drag ad drop of images betwee views. Zoom: Allows the user to zoom i o a image by clickig the left mouse butto o the view. If the magified image is larger tha the view widow i either directio, the poit o which the user clicks will jump to the ceter of the widow. To zoom out, click the right mouse butto (for a cotext meu click ad hold the right mouse butto for approximately oe secod). This same fuctioality is available whe the stadard selectio cursor is i use ad the user holds dow the Shift key while clickig. ViVA oly zooms i factors of two. This maitais the most direct relatioship betwee the image pixels ad the scree pixels. The rage of magificatio is from 1/128x to 32x. Magic Widow: Clickig ad holdig dow the left mouse butto o a Imageview widow will display a moveable widow i which the same image is viewed at twice the uderlyig resolutio. Pa: Whe this cursor is selected, clickig ad draggig with the left mouse butto o a Imageview widow will cause the image to move aroud (i.e., pa) withi the widow. This same fuctioality is available whe the stadard selectio cursor is i use ad the user holds dow the Cotrol key while clickig the right mouse butto PaxSca 3030CB / 4030CB Systems & Service Guide

59 Table 6-1 Cursors Click Result Regio of Iterest: The cursor ca be used to specify a regio o a image for statistical calculatios. The optios i the Aalysis meu ad the ROI Stats... butto o the Image Edit toolbar also become active. If a regio had bee previously specified, it is displayed agai o the image. Whe this cursor is ot selected, the ROI Stats... butto becomes Img Stats, ad statistics for the whole image ca be displayed by clickig it. Mouse ad Key Shortcuts Shortcut keys or hot keys provided i ViVA are summarized i the followig table. Table 6-2 Shortcut Key Combiatios Operatio Cursor Key Combiatio 6 Selectio/drag ad drop Ay Left mouse click Zoom i/out Shift + left/right click Pa Ctrl + left click Specify a regio of iterest ad show statistical iformatio. Ctrl + drag with left mouse butto Specify a regio of iterest costraied to be square. Chage widow/level usig the mouse. Movig the mouse left/right results i decrease/icrease of the widow. Movig the mouse dow/up results i decrease/icrease of the level. Shift + drag with left mouse butto Ctrl+Shift + left mouse butto dow Cotext Meus ViVA provides three cotext meus that apply o three differet types of images: Thumbview images, Imageview images ormally (Acquisitio toolbar preset), ad Imageview images i Defect Map Editor mode. To activate a cotext meu of a image, poit the mouse cursor at the image ad click right mouse butto. Whe the Zoom cursor is selected, hold the butto for about oe secod. The cotets of the meus are show i the followig figures: ViVA Help 6 59

60 Figure 6-8 Cotext Meu for Thumbview Figure 6-9 Cotext Meu for Imageview (Normal Mode) Figure 6-10 Cotext Meu for Imageview i Defect Map Editor Mode 6 60 PaxSca 3030CB / 4030CB Systems & Service Guide

61 Whe the Zoom cursor is active the right mouse butto is also used to zoom out; the shortcut meu ca be displayed by holdig the right mouse butto for about a secod. Nearly all cotext meu items are duplicated ad described elsewhere. Widow/Level Scroll Bars ViVA displays 16-bit images to displays which are commoly 8-bit. The widow/level cotrols select the rage of pixel values of iterest to the observer ad how pixel values are mapped to the more limited umber of gray levels which is discussed further below. Widow ad level ca be chaged i several ways usig cotrols o the Image Edit toolbar. Widow/Level cotrol is the oly form of image maipulatio that ca be applied to Thumbview widows. Widow/Level settigs are maitaied durig drag ad drop operatios. There are two scroll bars i the Image Edit toolbar that ca be used to chage widow ad level. By default the left scroll bar cotrols the widow ad the right the level. Optioally (usig the Edit W/L dialog), they may be set to cotrol the bottom (left scroll bar) ad top (right scroll bar) of the widow. Whe bottom/top are beig cotrolled by the scroll bars, holdig dow the Shift key while maipulatig either scroll bar causes the scroll bar buttos to move up ad dow together, which correspods to chagig the level while keepig the widow fixed. 6 Whe a image opes ViVA performs a umber of operatios. It uses a algorithm to attempt to determie the most likely widow ad level settigs that will work well for the image. It also sets the rage of the scroll bars so as to allow access to all pixel values i the image. I some cases it may be desirable to reduce the rage ad icrease the sesitivity of the scroll bars. The rage of the scroll bars may be modified for fier cotrol where eeded by the two buttos beeath the scroll bars. Both buttos operate o both scroll bars as follows: Decreases the rage of both scroll bars by a factor of 2. Icreases the rage of both scroll bars by a factor of 2. The ceter poit of each scroll bar s rage will, where possible, track the curret settig. Auto & Ivert W/L Auto W/L butto Clickig this butto applies the same automatic widow/level algorithm that is used whe images are opeed or acquired. It has the effect of resettig ay chages to widow/level that have bee made maually, ad also resettig the scroll rages to their iitial values. ViVA Help 6 61

62 Edit W/L Dialog Clickig EWL (Edit W/L) butto opes a dialog box which allows the user to adjust a umber of settigs relatig to the selected image. There are some exceptios as oted below where settigs are remembered for future images also. The dialog is show i the folloig figure. Figure 6-11 Edit Widow/Level Dialog Edit Values As oted above most of the settigs i this dialog apply oly to the selected image. The exceptio to this is how the scroll bars are used. They may be used either as Bottom/Top or Widow/Level. The relatioship betwee bottom(bot)/top ad widow(wi)/level(lev) is: wi = top - bot lev = (top + bot). 2 If required, actual values for the bottom/top or widow/level may be typed ito the appropriate edit box ad applied to the selected image oly. The check box Tur off Auto W/L.. turs off the automated widow/level feature i ViVA ad simply opes all future images with the curret values of widow ad level. Widow/Level Mappig All possible pixel values are mapped to a gray level typically ad are stored i a lookup table (LUT). Whe a image is displayed the appropriate gray level is selected from the LUT for each pixel. By default the relatioship betwee pixel values ad gray levels is liear; however, other optios also exist ad all are described ext: 6 62 PaxSca 3030CB / 4030CB Systems & Service Guide

63 Liear: A liear relatioship exists betwee the gray level (gry) ad the pixel value (pix); i.e. pix - bot gry = mxgry* top - bot If this equatio yields a value of gry greater tha the maximum umber of gray levels (mxgry = 255 typically) the the value of gry is held at mxgry; egative values are clipped at zero. PseudoFilm: This is iteded to simulate a film respose ad ca be tailored by the user if desired. The relatioship is: gry = mxgry * (1 - exp((-x)/y)) There are two user defied values which cotrol the behavior of this equatio. Presetly these are oly settable by maually editig the viva.ii file. They are: PseudoFilmCostat (pfc) ad PseudoFilmScalePct (pfs*100) foud i the [GammaSettigs] sectio. I the above equatio, the expoetial umerator is give by: X = pix - pfs * bot ad the deomiator by: Y = pfc + pfs * (top - bot) Ay egative values (for pixel values below bot) are replaced by zero. The mai cotrol is exerted by the deomiator Y. The default is to set pfs=0.67 (67 i the viva.ii file) ad pfc=0. I this case widow/level settigs behave ormally. Settig pfs=0 ad puttig i a value for pfc, e.g.500, will result i a fixed respose curve idepedet of the widow/level settigs. Itermediate behavior may be obtaied by settig both parameters to o-zero values. If both parameters are set to zero the the default values are applied. 6 No-Liear (ATa/S-curve): This is based upo the trigoometric arctaget fuctio. For each pixel value we calculate a value gval give by: (pic - lev) gval = (1/π a ta 2 wi The values of gval obtaied from this equatio always lie withi the rage 0-1, but the actual rage is geerally smaller depedig o the values of wi ad lev. A liear trasformatio is applied to gval such that the maximum rage of possible pixel values produces the maximum rage of possible gray levels. The above three resposes are illustrated i the followig figure for particular values of widow ad level settigs. ViVA Help 6 63

64 Figure 6-12 Gray Level Mappigs for Liear, PseudoFilm ad Ata/S-curve GammaCurve: Oe additioal gray level mappig optio is available. This allows the user to graphically set the desired curve as approximated by multiple liear sectios. Clickig o the butto Set Gamma Curve opes a dialog box where the gamma curve ca be set by draggig markers alog lead lies. The larger (red) markers are iterpreted as bottom ad top. Figure 6-13 Gamma Curve Adjustmet Dialog White Area Blakig Whe oly a relatively small part of the image is of iterest ad a substatial part of it was o-absorbig to X-rays, resultig i a expasive white area, white level blakig may be useful. Whe activated, the white level blakig fuctio allows the user to specify a threshold value above which lookup table values are replaced with the replacemet value. The result is a overall image i which the surroudig white areas do ot detract from the regio of iterest. The et effect of the threshold ad replacemet values will deped o which widow/level mappig is selected, as well as the bottom/top values. Chages made will be applied oly to the selected image PaxSca 3030CB / 4030CB Systems & Service Guide

65 Acquisitio Meu/Toolbar Commuicatio Lik ViVA may be used to cotrol a umber of receptors. Its origial missio was to cotrol receptors which use a separate Commad Processor (CP) box, ad commuicatio is the via the CP by meas of the etheret lik. The followig discussio makes this assumptio though i some cases where there is o CP, commuicatio may occur differetly. Whatever the physical attributes of the receptor, the ope lik commad has the effect of establishig commuicatio betwee ViVA ad the receptor, ad performig ay ecessary iitializatio actios. The fuctios i the Acquisitio meu are desiged to cotrol the PaxSca Commad Processor ad to obtai data from it. This meu is show i the followig figure as it would appear with o lik ope: Figure 6-14 Acquisitio Meu 6 A subset of these fuctios is placed o the Acquisitio toolbar for quick access. Before ay acquisitio activity a lik must be opeed which establishes commuicatio over the etheret lik to the receptor. Oly oe istace of ViVA ca lik to the Commad Processor at ay give time. Before attemptig to ope a lik to a Commad Processor system esure that IP address settigs i the Prefereces dialog have bee set as appropriate. The Acquisitio toolbar as it appears with o lik ope is show i the followig figure: Figure 6-15 Acquisitio Toolbar without lik ope The dropdow box called Acquisitio Mode serves dual purposes. Whe o lik to a receptor is ope, the dropdow box may be used to sed the ope lik commad as idicated i the figure; alteratively the ope lik commad may be selected from the Acquisitio meu. Whe a lik is ope it appears as follows where the mode ame i use appears i the dropdow box: ViVA Help 6 65

66 Figure 6-16 Acquisitio Toolbar with lik ope Whe a lik is ope, the Acquisitio Mode dropdow box may be used to select a mode if the receptor cofiguratio provides multiple modes. The buttos are show eabled with the lik ope which is typical, but ote that the Trasmit Image butto is oly eabled whe a image is selected. The Ope/Close lik optios i the Acquisitio meu are dyamically labeled so that oly the appropriate optios are displayed ad fuctioal. For example, after a Etheret lik is ope: Ope Etheret Lik is chaged to Close Etheret Lik To check the status of the commuicatio lik betwee ViVA ad the Commad Processor, choose Acquisitio Check Etheret Lik. To termiate the commuicatio lik, choose Acquisitio Close Etheret Lik. The Commad Processor ca be reset to a kow state by choosig the Acquisitio Reset State optio. The system will retur to the default operatig mode, which is the first mode i the Acquisitio Mode selectio list. If the coectio is lost ad the system is ot i sychroizatio with the Commad Processor, choose Acquisitio Reset Lik to permit the restart of commuicatio without termiatig ViVA. This commad will close all liks ad clears all iformatio obtaied from the Commad Processor. Choosig Acquisitio Ope Etheret Lik will establish aother lik. Image Acquisitio To iitiate image acquisitio, select Acquisitio Acquire Image from either the toolbar or meu. Oce the acquisitio is complete, the user may capture a image from the selectig Acquisitio Retrieve Image from either the toolbar or meu. I Radiography modes, the image is retrieved automatically. The dialog show below opes which allows the user to iput commets ad other techique iformatio: Figure 6-17 Image Ifo: User Iput 6 66 PaxSca 3030CB / 4030CB Systems & Service Guide

67 This iformatio may also be etered or edited later usig the View Image Iformatio commad. This dialog may be tured off for future image retrievals if required by checkig the Do ot display.. check box ad the clickig OK. Previously retrieved images may be set to the output buffer of the Commad Processor, where it takes the place of the last image acquired. First, select the required image by clickig o it i the ViVA iterface, the select Acquisitio Trasmit Image. Offset & Gai Calibratio Correctig for o-uiform pixel respose is essetial to obtaiig good quality images. Offset calibratio must be performed wheever the CP is powered up ad geerally it is desirable to perform offset calibratios regularly durig use for optimium results. Gai calibratios eed ot be performed early so ofte, ad the last gai calibratio for each mode is stored by the CP whe powered dow. To iitiate Offset or Gai calibratio, choose Acquisitio Offset Calibratio or Acquisitio Gai Calibratio from the meu; offset calibratios may also be iitiated from the toolbar. 6 Offset calibratios are completely automated, ad require o further user itervetio to complete. Gai calibratios require X-ray exposure with o object i the beam. Simply follow the o-scree prompts, ad expose whe prompted to do so. Rad modes allow the user to expose multiple times to allow statistical averagig of the gai image. Offset & Gai Calibratio with 3030CB / 4030CB Receptors 3030CB / 4030CB receptors provide dual gai modes. Calibratio is accordigly more complicated. Offset calibratios remai autoomous, but for dyamic gai modes multiple calibratios occur; a secod forced logai calibratio is performed i additio to the ormal oe (which always occurs at high gai for all pixels i the absece of X-rays). For dual read modes, a sigle calibratio provides offsets i both gai settigs. Gai calibratio requires the same offset operatios as above for dark field acquisitio followed by flat-field acquisitio with x-ray settigs appropriate for each gai. Gai calibratio should always be doe at cout levels low eough to avoid ay possible saturatio, but high eough to achieve good statistical measuremet of pixel respose. For 14-bit receptors a offset-corrected value i the rage is suggested. ViVA Help 6 67

68 The oscree prompts guide you through the process with oscree prompts such as that i the followig dialog: Figure 6-18 Gai calibratio dialog Gai Ratio Calibratio The Acquisitio Gai Ratio Calibratio commad ivokes a additioal calibratio which is available oly i dual read modes which requires a sigle X-ray exposure adjusted ot to saturate at either gai. This allows calculatio of the gai ratio. Figure 6-19 Acquisitio meu dual read modes 6 68 PaxSca 3030CB / 4030CB Systems & Service Guide

69 Exteded Gai Calibratio The Acquisitio Exteded Gai Calibratio commad ivokes a additioal calibratio which is available oly i dyamic gai modes which requires multple exposures at differig X-ray levels. Figure 6-20 Acquisitio meu dyamic gai modes 6 This commad brigs up the followig dialog: Figure 6-21 Exteded Gai Calibratio dialog ViVA Help 6 69

70 This calibratio is similar to other gai calibratios except for the multi-dose level requiremet. It provides prompts as to the X-ray level required depedig o the butto selectio i Acquisitio Settigs. As acquisitios are doe it steps through the differet Offset ad X-ray levels but the user may choose to do the acquisitios i aother order just by clickig the appropriate butto at ay time. All levels except X-ray1 are required before the Calibrate butto is eabled. X-ray1 is used oly for the gai ratio determiatio which is eeded ifrequetly. This calibratio actually ivolves switchig betwee ormal ad forced lo-gai states for each Xray level. It may be more accurate to acquire data by switchig back ad forth several times, ad the # of cycles field allows this parameter to be set. calibratio statistics whe available are show for the selected Offset or X-ray level. System Settigs The Acquisitio System Settigs... commad operates slightly differetly i K.04 ViVA with 3030CB / 4030CB support. Normally this commad is ot eabled whe o lik is ope. For 3030CB / 4030CB systems, however, it is eabled ad brigs up the followig dialog: Figure 6-22 System Settigs No Lik Ope 6 70 PaxSca 3030CB / 4030CB Systems & Service Guide

71 The dropdow box labelled Imager Serial Number allows a selectio to be made amog available receptors i the IMAGERs directory. However, if the receptor cofiguratio loaded ito the Commad Processor has a serial umber set, the this selectio is overridde ad the oe that will be used is the oe i the receptor cofiguratio file. Whe there is a ope commuicatio lik to the Commad Processor, the Acquisitio System Settigs... commad is active; it brigs up the followig dialog: Figure 6-23 System Settigs Lik Ope 6 O the left side of the dialog box, uchageable iformatio about the system is displayed. O the right side are Image Correctios settigs. These check boxes allow the user to select which image correctio algorithms are applied i the Commad Processor. If the Commad Processor has a optioal ABS video board, the dialog box will iclude the ABS Board group ot displayed i Figure 19, which icludes a additioal correctio algorithm ad vertical/horizotal reversal check boxes. Mode Settigs With a ope commuicatio lik, the Acquisitio Mode Settigs... commad is active; it brigs up the Mode Settigs dialog. At the top of the dialog box is a selectio list for the operatioal mode. The rest of the settigs show i the dialog box apply oly to the selected mode. The Mode Settigs dialogs are show i the followig two figures: ViVA Help 6 71

72 Figure 6-24 Mode Settigs Fluoroscopy modes Figure 6-25 Mode Settigs Radiiography modes 6 72 PaxSca 3030CB / 4030CB Systems & Service Guide

73 Iformatio Iformatioal settigs are ot chageable except for the frame rate ad user syc. Calibratio Setup The user may specify the umber of frames used durig calibratio ad the settigs for the optioal automatic offset calibratio. I additio provisio is made for a offset calibratio shift to be applied durig offset calibratios. This will add a fixed offset to every pixel i the whole image if chaged from the zero default. Acquisitio/Display This group shows differet settigs depedig o whether a mode with fluoroscopy (cotiuous) acquisitio or radiography (accumulatio) acquisitio type is selected. For a fluoroscopy mode: the user ca set the recursive filter fractio. For a radiography mode: the user ca choose betwee lettig the system automatically sese X-rays start maually. Acquistio modes subdivide further by whether the user wishes to have a predetermied umber of frames accumulated (summed) or cotrol stop maually. The Scalig Type optio allows the fial image to be scaled to brig media pixel values ear the target value. Whe Up is checked scale factors greater tha 1 are allowed; whe Dow is checked scale factors less tha 1 are allowed. If both scalig optios are selected, the resultat image may be scaled up or dow, ad if either is checked o scalig occurs. 6 Gai Settigs These allow the user to set a Pixel Saturatio Value above which pixel values will be replaced by the Pixel Replacemet Value. Rad AutoSave This commad allows the user to set up a file path ad base ame which is used whe makig Rad mode acquisistios. Each time Acquire Image is pressed the image is automatically retrieved ad saved. For example if the base ame is radauto the first acquisitio might result i a file radauto 001.viv. Hardware Hadshakig Whe the hardware cofiguratio permits a X-ray valid sigal to be set to the commad processor, this meu item should be checked so that ViVA does ot attempt to sed the correspodig software hadshakig calls. ViVA Help 6 73

74 Video Meu/Toolbar ViVA K.04 supports operatio with oly Bitflow frame grabber cards. Curretly the R3-PCI-DIF is supported for use with the stadard (CP1) Commad Processor. A camera lik card is also supported for use with CP1B. Durig istallatio a optio is give to istall the Bitflow support software. Rad Modes Most of this Video Meu/Toolbar sectio is applicable oly to Fluoro modes of operatio. ViVA automatically takes advatage of the frame grabber where available to speed retrieval of rad images immediately after acquisitio ito a ew thumb pae; this is faster ad more coveiet tha retrieval over the etheret coectio. The Record Sequece commad will remai iactive i Rad modes. All rad acquisitios must be iitiated usig Acquire Image. Recordig Sequeces This ad followig sectios are applicable to Fluoro modes oly. Oce the frame grabber ad its associated driver/software libraries are properly istalled, ViVA ca record sequeces i ay Fluoro mode. The Video toolbar is by default docked at right side of the ViVA widow. The followig figure shows the Video toolbar with aotatios to show what each butto does: Figure 6-26 Video Toolbar May of the buttos also have duplicate commads i the Video meu. With the frame grabber istalled ad a Commad Processor lik established, the Record Sequece butto becomes active (o a color moitor it will be gree with a red border) PaxSca 3030CB / 4030CB Systems & Service Guide

75 ViVA uses two grab image buffers to which the frame grabber has Direct Memory Access (DMA). ViVA also sets up a umber of sequece or copy buffers to which data are copied durig the live data acquisitio. The legth of the sequece that ca be recorded depeds upo how may sequece buffers are allocated which i tur is limited by the physical memory (RAM) preset o the computer. By default, while recordig, ViVA will copy frames cotiuously ito the sequece buffers i a circular maer overwritig the first frame oce the last buffer is filled. The first time after each lauch that the Record Sequece butto or meu item Video Record Sequece is selected, a dialog box will appear. This dialog ca also be opeed at ay time from Video Allocate Buffers..., ad is show i the followig figure: Figure 6-27 Allocate Buffers Dialog Box 6 The Number of Frame Buffers which as metioed above determies the legth of sequece that ca be captured. The umber that ca be allocated is limited by available memory. Oce acquisitio begis, frames are displayed i a Thumb View pae which ca be dragged ad maipulated like a ormal image pae. However, the overlay showig certai image iformatio is ot available durig capture. The acquistio may be stopped by the Stop Sequece commad from either the toolbar or meu. Durig recordig ViVA will apply its automatic widow/levelig routie oly if the overall image brightess chages sigificatly. If you wat to avoid ay automatic widow/levelig activity, set the levels you wat usig Edit W/L... i the Image Edit toolbar. ViVA will ot chage them agai as log as the pae remais ope. ViVA Help 6 75

76 Playig Sequeces Oce a sequece is i memory, it may be played back by the Play Sequece meu or toolbar item. Whe playig back the playback speed defaults to the recorded speed but may be varied usig the up/dow arrow buttos. These vary the speed by factors of 2. The actual speed obtaied may be limited if it is ot possible to repait the scree quickly eough. This will be iflueced by various factors such as the processor speed, scree resolutio, pae size ad umber of paes displayig the video. The sequece may also be stepped oe frame at a time from the toolbar. More Video Optios: Video Meu Some of the items i the Video meu have already bee discussed. This sectio will describe the remaiig selectios. The Video meu is show i the followig figure as it would appear with a sequece already loaded i memory, a lik to a commad processor ope ad a frame grabber card properly istalled: Figure 6-28 Video Meu Load Video Sequece... This commad allows a saved video sequece (.seq file) to be loaded ito memory. A dialog - as show i the followig - will ope to allow a subset of the etire file to be opeed as required: Figure 6-29 Sequece Subset Ifo 6 76 PaxSca 3030CB / 4030CB Systems & Service Guide

77 Depedig o the amout of RAM o the computer ad the legth of the sequece file, the segmet you ca ope may be limited to less tha the whole file. The File Ope... commad may be used istead of Video Load Video Sequece...; the oly differece is that i the latter case the oly file filter vailable is.seq. Save Video Sequece... This commad is equivalet to File Save As..., ad allows a sequece i memory to be saved. The first dialog to ope is similar to that i Figure 25, allowig a subset of the etire sequece to be selected if required. Subsequetly a file save dialog will ope, ad the sequece may be saved as either a.seq file or as a.avi file. The.seq saves the image data i a ucompressed 16-bit format with the same header as is used for.viv files. The.avi format is a stadard format that ca be played for example o Microsoft Widows Media Player. If the.avi file filter is chose aother dialog will ope as show below: Figure 6-30 Set AVI Quality 6 Files stored as.avi store the data i a lossy compressed 8 bit format usig the widow/level selected. The AVI quality settig determies how much compressio is applied, tradig file size for quality. The frame rate is also selectable i case the user would like to play back the AVI at a differet speed from that recorded. Get Frame from Sequece... This commad simply gets a idividual frame ad displays it i a ew Thumb View pae. Capture first N frames This optio allows the user to tur off the feature whereby frames are recorded i circular fashio - overwritig the first frames captured whe all the sequece buffers are filled. Whe this item is checked, capture stops after all the buffers are filled. The N may be replaced by the actual umber of buffers allocated i the meu as is the case i Figure ViVA Help 6 77

78 Test Image Mode This allows a test patter or other image to be retrieved from the commad processor; all frames captured are the same. You ca for example use Trasmit Image i the Acquisitio toolbar to trasmit a test patter for subsequet capture via the frame grabber. After chagig modes or powerig up the commad processor you should, i Test Image Mode, perform the followig steps: 1. Press Acquire Image i the Acquisitio toolbar followed by Stop i the Fluoroscopic Acquisitio dialog. 2. Trasmit Image as required. 3. Press Record Sequece ad the Stop Sequece to capture the image via the frame grabber. Test Image Mode must be used with care. Sice it disables commads to ru the commad processor it is also possible for the commad processor ad ViVA to get out of sychroizatio with respect to which mode is operatig. If you have Test Image Mode selected, you must ru the commad processor usig Acquire Image i the Acquisitio toolbar before ruig video if you have just powered up or chaged modes. Disable Display Durig Capture As idicated this optio disables the display update durig capture. It will rarely be foud useful sice ViVA already gives priority to the activity of copyig data to the sequece buffers over refeshig the display. Allocate Buffers This dialog is discussed above uder Recordig Sequeces. Iitialize Video This commad will ot typically be foud useful sice ViVA automatically itializes the Video if a frame grabber istallatio exists. However, frame grabbers do ot geerally permit more tha oe process (applicatio) to take cotrol at a time. If aother applicatio is usig the frame grabber whe ViVA lauches, ViVA will ot be able to iitialize the video ad this meu item will be active provided a lik to a commad processor exists. This could be useful if you wat to switch operatio betwee applicatios. Dispose Video This commad causes ViVA to reliquish cotrol of the frame grabber ad allows aother applicatio to use it. Reset Video This commad simply combies the Dispose Video ad Iitialize Video commads. It may be useful if the frame grabber operatio becomes ustable PaxSca 3030CB / 4030CB Systems & Service Guide

79 Aalysis Meu: Image Statistics ROI Basic The Aalysis meu allows the user to obtai statistical iformatio o a specific regio of a image called the Regio Of Iterest (ROI). Geerally the commads relatig to the ROI are ot active uless the ROI cursor is selected (see Table 2). Except for 2520M receptors, the Edit Toolbar cotais a butto at the top which is labeled either Img Stats or ROI Stats. It will be Img Stats uless the ROI cursor is active ad a ROI draw. This butto allows statistics for the whole image to be displayed at ay time. A ROI may be selected by clickig the left mouse butto aywhere i a image pae ad holdig while a rectagle is defied. The ROI shows as a blue rectagle overlay which persists after the mouse butto is released util a differece cursor is selected or ew ROI draw. Eve whe ot displayed, the last ROI coordiates are remembered ad displayed if the ROI cursor is reselected. If you attempt to drag outside the image, the rectagle chages to red ad saps to the image border if the mouse is released. If you hold the Shift key while draggig, the ROI will be square. 6 Basic Meu Commads Aalysis Select Whole Image allows the user to select the whole active image as a regio of iterest. Aalysis Clear ROI allows the user to clear the selected ROI. Aalysis Show ROI Statistics... allows the user to display statistical iformatio. Alteratively this commad may be ivoked from the ROI Stats... butto o the Edit toolbar or the ROI Stats... meu item of the Cotext Meu for Image View. Ay of these will result i the dialog show i the followig figure: ViVA Help 6 79

80 Figure 6-31 Regio of Iterest Statistics Dialog Box The user ca also immediately obtai this iformatio after drawig a regio by holdig dow a Ctrl key while draggig the mouse. The Ctrl key must be pressed ad held dow before draggig to specify a regio of iterest. ROI Dialog The regio of iterest may be redefied by eterig two ew diagoal poits of a ew regio directly ito the field 01 edit boxes. The Apply butto causes recalculatio of all statistical iformatio usig the curret two poits specifyig a regio. There are four buttos which provide for additioal output: The Histogram butto performs a histogram aalysis of the pixels i the ROI ad puts the output ito a tab-delimited text file. (Tab-delimited text files may be coveietly imported ito Microsoft Excel usig the file ope text filter ad acceptig defaults.) The Image butto allows the ROI to be saved i a image format. The Text butto allows savig the ROI pixel values to a text file formatted i rows ad colums as i the ROI. Agai it is tab-delimited for coveiet import to Microsoft Excel. The Prit butto simply outputs the statistical iformatio from the dialog to a priter PaxSca 3030CB / 4030CB Systems & Service Guide

81 The statistical iformatio provided o this dialog box is explaied i the followig table: Table 6-3 Regio of Iterest Statistical Iformatio Name Format Descriptio 01. Regio of Iterest (x 0,y 0 ) to Two diagoally disposed poits that (ROI) (x 1,y 1 ) defie the ROI rectagle. 02. Width ad Height iteger x Width ad height dimesios of Regio iteger of the ROI. 03. Ceter of ROI (x,y) Ceter locatio of the ROI. 04. Number of Pixels iteger Number of pixels foud i ROI. i ROI 05. Number of Defective iteger Number of defective pixels foud i Pixels i ROI the ROI. These are pixels with the value that ViVA itreprets as defective. 06. Percet of real Percet of the regio over the whole ROI/Image image Sigal/Noise real Defied by formula average/stadard Ratio i ROI deviatio. 08. Maximum Pixel Maximum pixel value first foud i Value i ROI (x,y) the ROI. 09. Miimum Pixel Miimum pixel value first foud Value i ROI (x,y) i the ROI. 10. Total of Pixel iteger Total of all pixel values foud Values i ROI i the ROI. 11. Average of Pixel real Average of pixel values foud Values i ROI i the ROI. 12. Stadard real Stadard deviatio of pixel values i Deviatio i ROI the ROI. 13. Stadard Deviatio real Stadard deviatio of the mea values of Row Meas of the rows. 14. Stadard Deviatio real Stadard deviatio of the mea values of Colum Meas of the colums. The coordiates (x,y) of a poit ad the dimesio width by height are limited by the size of a image. Specifically, rages of a pair (x,y) are from 0 to (width -1) ad 0 to (height -1), respectively. Pixel values are i rage from 0 to maximum pixel value. ViVA Help 6 81

82 RoiList Commads The RoiList commads greatly exted the usefuless of the ROI aalysis feature. This feature allows you to set up multiple ROIs ad the apply to multiple images. Whe a ROI is selected you may add it to the RoiList by selectig Aalysis Add ROI to RoiList. This saves the ROI coordiates ad causes the ROI to be displayed as a cya rectagle. By redrawig the ROI ad addig to the RoiList, you ca select mulitple ROIs. The active ROI is the oe i blue ad is ot ecessarily a member of the RoiList util you add it. The ROI statistics dialog will always refer to the active ROI. Whe a RoiList has bee established by selectig Aalysis Add ROI to RoiList oe or more times, it ca be applied i a batch-like maer to multiple images. To apply the RoiList, select Aalysis Apply RoiList... This will first ope a file save dialog box for the output file - agai tab-delimited text. If the active image is a idividual image - as opposed to a video sequece - aother file dialog box will the ope. This dialog allows you to select multiple image files. All the images selected must be.viv or.raw ad must have the same image dimesios as the image i the selected image pae. Statistical iformatio will be determied for all the ROIs i the RoiList ad for each image selected i the file dialog ad output to the text file. The ROIList may be saved to ad retrieved from a text file (which ca be edited if required) usig the commads Aalysis Save RoiList to File ad Aalysis Load RoiList from File Notes o ROIList Use: If the selected image is a video pae ad ot a idividual image pae, the istead of the secod file dialog box you will be asked to select a video segmet for processig. The actual image i the image pae is ot ecessarily processed. Oly the image files or the video segmet selected are processed. The output will by default cosist of two fields for each ROI: 11. Average of Pixel Values i ROI ad 12. Stadard Deviatio i ROI. Notice that i Figure 31 these two fields have checks i the adjacet check boxes. You ca select ay or all or the fields to be output usig the check boxes. (01. Regio of Iterest has o check box but this iformatio is always writte to the text file.) The status of the check boxes is remembered whe the ROI dialog is closed ad this defies the fields that are output. ViVA will remember which fields were last selected eve betwee lauches. The RoiList itself is more volatile tha the check box iformatio. RoiList iformatio is actually specific to each image pae. It will, however, geerally be remembered eve if you close the image i the image pae. If you attempt to drag a image to the pae that has differet dimesios tha the oe for which the RoiList was defied, a message box will war you that this actio forces a RoiList reset. All RoiList iformatio is lost whe ViVA closes (but ot the check box iformatio). The RoiList may be reset at ay time by Aalysis Reset RoiList PaxSca 3030CB / 4030CB Systems & Service Guide

83 Tools Meu The Tools meu is cosists of a umber of sub-meus each with multiple commads; these will geerally cosist of the followig which are described i detail below: Receptor Commad Processor Defects Image Operatios Coe Beam CAUTION: May of the commads i this sectio are iteded for Egieerig use ad should be used oly by experieced users or uder the directio of Varia Medical Systems techical staff. Receptor 6 Aalog Offset Calibratio The Aalog Offset Calibratio... commad allows the user to chage aalog offset settigs ad perform a aalog offset calibratio. Whe selected, this optio will display a Aalog Offset Settigs dialog box as show i the followig figure: Figure 6-32 Aalog Offset Settigs ViVA Help 6 83

84 The Apply or OK butto oly updates the settig iformatio from the Edit boxes at the Commad Processor without performig a calibratio. The Calibrate butto iitiates a aalog offset calibratio. A aalog offset calibratio rus autoomously; it is a iterative process, ad if the target rage is reached for all ASICs before completig the limitig umber of iteratios, it termiates early. After a aalog offset calibratio is doe, it is essetial to perform a gai calibratio before images ca be properly corrected. DCDS Eable The Set DCDS Off commad allows DCDS to be temporarily disabled which is useful i coectio with performig aalog offset calibratios. DCDS will tur o agai automatically whe the mode is chaged, or whe Offset/Gai calibratio is performed. Commad Processor Display Test Patter If ViVA has a ope coectio to the Commad Processor, choosig the Display Test Patter optio causes the Commad Processor to display a test patter cosistig of eight horizotal bars of equal height, with liear steps i itesity from zero at the top of the image, to 3,584 couts at the bottom. The image size idicated relates to the curretly selected mode. Write ABS MailBox The Write ABS MailBox... commad should oly be used uder the directio of Varia Medical Systems techical staff. Trasmit Files The Trasmit Files... commad allows the user to trasmit ew files to the Commad Processor. Curretly, ViVA ca trasmit the followig file types: System Software file Global Cotrol Firmware file Receptor Firmware file Receptor Cofiguratio Data file Base Defect Map Image file Gai Calibrated Image file Offset Calibrated Image file The file type to be trasmitted should be checked, the browse to the file itself, ad click Trasmit PaxSca 3030CB / 4030CB Systems & Service Guide

85 Retrieve Files The Retrieve Files... commad allows the user to retrieve a file from the Commad Processor. It operates similarly to the Trasmit Files fuctio. Debug Verbosity Debug Verbosity ca be toggled o/off. Turig this optio o causes the Commad Processor to prit debug iformatio over a serial port which ca be captured with Hypertermial for example. Havig debug verbosity set to Off (default) will improve system performace. I additio ViVA will write a file CmdTestLog.txt to the ViVA directory; it is writte whe Debug Verbosity is tured off, ad ay previous file overwritte. It cotais a log of calls made by ViVA while Debug Verbosity was o icludig parameters ad retur values. Reset The Reset commad seds a commad to the Commad Processor to re-boot ad the lik from ViVA is also reset. Eable IPU This is a rarely eeded, oly for specialized receptor cofiguratios. 6 Defects Defect Map Editor The Defect Map Editor is ivoked by choosig Tools Defects Defect Map Editor... This will switch ViVA from image viewig mode to image editig mode. The Acquisitio toolbar is replaced by the Defect Map Editor toolbar. The Status Bar displays the curret mode i the Commad Processor. All images i Image View are closed ad Image Layout is set to Two-Image Layout. ViVA the retrieves the Base Defect Map image ad the Auxiliary Defect Map image from the Commad Processor ad displays them i the Thumb View ad the Image View. The Base Defect Map image is placed i the right pae, ad the Auxiliary Defect Map image is placed i the left pae. ViVA Help 6 85

86 Figure 6-33 Defect Map Editor Screeshot By default, ViVA displays good pixels i black ad defective pixels i white. Pixel Editig O the leftmost side of the Defect Map Editor toolbar is the pixel list which cotais all edited pixels as they are marked from good to defective. The list cotais oly maually-edited pixels. Defective pixels foud o the retrieved or ope image are ot icluded i the list. With the shortcut meu: Right click to brig up the shortcut meu. Select Mark Pixel Defect. If the pixel is already defective, the word Defect will be replaced by the word Good i the meu item. With mouse actios: To mark a good pixel as defective or a defective pixel as good, simply poit the cursor at the pixel ad click the left butto. Whe a good pixel is marked as defective, the pixel is placed o the pixel list ad whe a defective pixel is marked as good, the pixel is deleted from the pixel list. Editig the defect map by direct mouse actios requires that the active cursor be the Stadard Selectio. With keyboard actios: Similar to the mouse actios, the Arrow keys ad the Eter key ca be used to edit a pixel. Use the arrow keys or the mouse to poit at a desired pixel. Press Eter toggle to the pixel from good to defective, or defective to good PaxSca 3030CB / 4030CB Systems & Service Guide

87 With the pixel list: To add a pixel oto the pixel list, select <Pixel>, type the coordiates of the pixel i the poit form (x,y), the press the Tab key to ed the additio. To delete a pixel, select the desired pixel, press the Backspace key ad press the Tab key to ed the deletio. To chage the coordiates of a pixel, select the pixel, edit the x ad y coordiates, ad press the Tab key to ed the chage. Row Segmet Editig The secod dropdow list i the Defect Map Editor toolbar is the row segmet list. It cotais defective row segmets marked i the defect map editor. As with idividual pixels, row segmets foud o the retrieved or ope image are ot icluded i the list. With the shortcut meu: Right click to brig up the shortcut meu. Select Mark Row Defect. If the row is already defective, the word Defect will be replaced by the word Good i the meu item. With mouse actios: To mark a good row segmet as defective or a defective row segmet as good, simply poit the cursor at the row ad the click o the left butto while holdig dow the Shift key. Whe a row segmet is marked as defective, the segmet is placed o the row segmet list ad whe a defective row segmet is marked as good; the segmet is deleted from the row segmet list. With keyboard actios: Similar to the mouse actios, the arrow keys ad the Eter key ca be used to edit a row. Use the Arrow keys or the mouse to poit at a desired row. The press Eter while holdig dow the Shift key to toggle the whole row from good to defective or defective to good. With the row segmet list: 6 To add a row segmet to the row segmet list, select <Row Segmet>, type i the coordiates i the row segmet format (x 1,y) to (x 2,y) ad press the Tab key to ed the additio. To delete a row segmet, select the desired row segmet, press the Backspace key ad press the Tab key to ed the deletio. To chage the coordiates of a row segmet, select the row segmet, edit the x ad y coordiates ad press the Tab key to ed the chage. ASIC-wide defects represet a special case of row defects. Some additioal commads allow ASIC-wide defects to be coveietly marked. From the keyboard press Shift/A or from the shortcut meu select Mark Asic Segmet Defect. ASIC-wide defects are listed i the row segmet list box. Colum Segmet Editig The third dropdow list i the Defect Map Editor toolbar is the colum segmet list. It cotais defective colum segmets marked i the defect map editor. As with idividual pixels ad rows, colum segmets foud o the retrieved or ope image are ot icluded i the list. ViVA Help 6 87

88 With the shortcut meu: Right click to brig up the shortcut meu. Select Mark Colum Defect. If the colum is already defective, the word Defect will be replaced by the word Good i the meu item. With mouse actios: To mark a good colum segmet as defective or a defective colum segmet as good, simply poit the cursor at the colum ad click the left butto while holdig dow the Cotrol key. Whe a colum segmet is marked as defective, the segmet is placed o the colum segmet list ad whe a defective colum segmet is marked as good, the segmet is deleted from the colum segmet list. With keyboard actios: Similar to the mouse actios, the Arrow keys ad the Eter key ca be used to edit a row. Use the arrow keys or the mouse to poit at a desired row. Press Eter while holdig dow the Cotrol key to toggle the whole colum from good to defective, or defective to good. With the colum segmet list: To add a colum segmet oto the colum segmet list, select <Colum Segmet>, type i the coordiates i the colum segmet format (x,y 1 ) to (x,y 2 ) ad press the Tab key to ed the additio. To delete a colum segmet, select the desired colum segmet, press the Backspace key ad press the Tab key to ed the deletio. To chage the coordiates of a colum segmet, select the colum segmet, edit the x ad y coordiates, the the Tab key to ed the chage. O the 4030A receptor, because of the split readout, colum defects oly exted to the midway poit of the imager. If the cursor is i the top half of the image, the colum defect will be restricted to the top half; or if the cursor is i the bottom half, the colum defect will be restricted to the bottom half. OR Image To add all defective pixels o the Auxiliary Defect Map image o the left Image View pae to the Base Defect Map image o the right of the Image View pae, click OR Image. This commad is useful whe there is a existig image with defective pixels that ca be added oto the Base Defect Map image. The user simply opes a image as usual, the drags ad drops the thumbail view of the image oto the left pae before addig the two images. Retrieve To retrieve a ew Base Defect Map image ad a Auxiliary Defect Map image, click Retrieve. This commad deletes ay previous chages to the defect maps ad allows the user to start editig agai without termiatig Defect Map Editor mode. Trasmit To trasmit the Base Defect Map image to the Commad Processor, click Trasmit. This moves the image o the right Image View pae to the Commad Processor ad overwrites the curret Base Defect Map image with the ew oe PaxSca 3030CB / 4030CB Systems & Service Guide

89 Close To close the Defect Map Editor ad switch back to stadard ViVA viewig mode, click Close o the Defect Map Editor toolbar. All images i the Thumb View ad the Image View remai uchaged. The Defect Map Editor toolbar is replaced by the Acquisitio toolbar. Defect Map Threshold Tool A simple but effect method for geeratig a defect map is to set upper ad lower thresholds for defects i a acquired flat field image. The Defect Map Threshold Tool is ivoked by Tools Defects Defect Map Threshold tool... This brigs up the followig dialog box: Figure 6-34 Defect Threshold Tool 6 The threshold tool operates o the active image - which might be a flat field image - ad geerates a ew Thumb View image as its output. The ew image will cosist of zero pixel values everywhere except where a defective pixel is determied; the value for defective pixels is determied by the Defect Pixel Value i the dialog box or 1 for K.01 ViVA. Defective pixels are iferred to be those which have values below the Lower Threshold or above the Upper Threshold. It is geerally ecessary to trasmit defect images geerated usig the Threshold Tool via the Defect Map Editor ad NOT by Tools Commad Processor Trasmit Files... ViVA uses the value as the defective pixel value iterally but coverts to 1 for trasmittal to the Commad Processor. Whe you drag ad drop i the Defect Map Editor, ViVA checks the image ad if it detects that it cosists of oly 0 ad 1 will covert the 1 s to The followig message box is show whe this occurs: Figure 6-35 Defect Map Coversio Warig ViVA Help 6 89

90 Fid Noisy Pixels The purpose of the Fid Noisy Pixel... commad is to idetify pixels that may ot appear defective for each ad every frame, but over a umber of frames fluctuate sigificatly i itesity. The oisy pixel routie collects a umber of frames ad attempts to idetify oisy pixels statistically as those havig a relatively high stadard deviatio (SD) also referred to as sigma. The SD is calculated for each idividual pixel or bied groupig, accordig to the mode. The SD is formed o a temporal, ot spatial, basis as would be the case i ROI calculatios. Noisy pixel detectio is ivoked by Tools Defects Fid Noisy Pixels... Parameters are selected i the top sectio of the dialog box etitled Acquisitio, which is show below: Figure 6-36 Fid Noisy Pixels Dialog Acquisitio Each cycle will ivolve the acquisitio of the specified umber of frames, ad the retrieval of the last. This allows the user to spread the actual frames used i the computatio out over a larger umber of frames, which could be useful if the fluctuatios are clustered rather tha radom. Oe frame is retrieved for each cycle. I order to compute the SD effectively, it is suggested that at least te cycles be specified. For iitial familiarizatio purposes, five will be adequate. The acquisitio may take some time, particularly i modes where o biig is used ad will be essetially proportioal to the umber of cycles. The user may choose to save each idividually-retrieved frame to a disk file via the check box. This feature will probably ot ormally be selected. To begi acquisitio, click Acquire Noisy Pixel Data. The user is give the opportuity to save to disk the SD image formed. The SD image is actually the calculated stadard deviatio scaled by te to improve precisio. A Thumb View of the SD image is displayed PaxSca 3030CB / 4030CB Systems & Service Guide

91 Set Threshold ad Display Whe acquisitio is complete, a threshold ca be selected above which pixels are cosidered defective. Chagig the value of the threshold will ormally result i a correspodig chage i the idicated umber of pixels above the threshold. The displayed umber is updated wheever the threshold is chaged ad focus shifted away from the Set SD Threshold edit box; e.g., whe fiished typig, press the Tab key. Whe the required threshold has bee selected, a defect map ca be created by pressig Display Noisy Pixels. If this butto is clicked whe o acquisitio is curret (i.e. o acquisitio doe sice the dialog box opeed), the user is give a opportuity to select a previously acquired SD image from a disk file. Idetifyig Noisy Pixels Oe method to idetify oisy pixels requires the followig: Exitig the dialog box ad ispect the acquired SD image Magify some part of it ad look for a featureless (ormal) regio Use the ROI facility to evaluate the average SD ad the stadard deviatio of the SD itself i this regio Repeat i other areas to get good umbers for the average ormal SD ad its distributio, as idicated i the stadard deviatio box of the ROI dialog. 6 A good choice for the threshold will likely be ~6x the stadard deviatio of this distributio plus the average. This procedure is roughly that carried out by clickig the AutoSet butto. Updatig the Base Defect Map Whe the required threshold is idetified, the Noisy Pixel dialog box ca be reopeed. Data of iterest are reactivated by pressig the Display Noisy Pixels butto, ad selectig the appropriate file. Set the threshold ad click Display Noisy Pixels agai to esure the defect map is created at the required threshold settig. Whe the defect map is correct, dowload it to the Commad Processor by clickig OR With Aux Defect Map or OR With Base Defect Map. This results i the logical OR operatio beig performed with either the existig auxiliary defect map or the existig base defect map; the result is always a ew base defect map If the threshold value is chaged without creatig a ew map, ad the oe of the OR buttos clicked, a ew map is automatically created prior to updatig the base defect map. The result is dowloaded to the Commad Processor. ViVA Help 6 91

92 Image Operatios Add/Subtract The Add/Subtract... images commad allows the user to perform a arithmetic subtractio or additio of two images. This commad opes the followig dialog box: Figure 6-37 Image Arithmetic Dialog Images must be saved files i.viv or.raw format or.seq. ViVA obtais a resultat image by performig a subtractio or a additio o a pixel of a source image ad the correspodig pixel of a base image, plus a offset factor. These two images must be the same dimesios. A scale factor may also be applied i the calculatio as set i the dialog. If the optio Use Auto Offset Factor is checked, ViVA will use the smallest offset that prevets ay egative pixel values. The file ames of the forms Subtracted-Image- or Added-Image- where is a positive iteger, are used as temporary files durig a image arithmetic operatio. Do ot ame or store ay file i these forms uder the directory where the executable viva.exe is located. If the source images are sigle image files, the resultat image is displayed as a ew Thumb View image. If the source files are.seq files the the result is saved to a ew file. The Resultat Image status box idicates how ad where the result is located. Pixel Editor This tool may be useful to maually retouch images where there are a small umber of pixel defects. The commad Tools Image Operatios Pixel Editor... brigs up the followig dialog: 6 92 PaxSca 3030CB / 4030CB Systems & Service Guide

93 Figure 6-38 Pixel Editor Dialog The X ad Y coordiates of the pixel to be replaced must be etered ito the edit boxes. The Average Pixels at Displacemet edit box determies how the replacemet value is calculated. For example if this value is 1, the 8 earest eighbors are averaged. For a value 2, the 16 ext-earest eighbors are averaged etc. Add Offset to Pixels 6 The Tools Image Operatios Add Offset to Pixels... commad simply asks the user to specify a offset value that will be added uiformly to all pixels. Optimize Auto Level The Tools Image Operatios Optimize Auto Level... commad allows customizatio of the algorithm used i the Auto W/L (Image Edit toolbar) commad. To use this effectively it is suggested that a umber of varied images be opeed. The commad opes the followig dialog: Figure 6-39 Optimize Auto Level Parameter Dialog ViVA Help 6 93

94 Briefly the algorithm works by dividig the image ito regios ad attemptig to determie which are likely to be of greatest iterest. The regios determied to be of greatest iterest are used to form a histogram. The bottom ad top of the widow are the set at poits which trucate a specified % of the histogram area at the low ad high eds. The parameters i the dialog box have the followig sigificace: # of regios - is the total umber of regios the image is divided ito. # used for histogram - is the umber used fially i determiig the widow ad level settigs. # of border regios igored - specifies how may regios aroud the image periphery are precluded from cosideratio. # of hi/lo regios igored - specifies the umber of the brightest ad darkest regios that are also igored. % of histogram lo trucated - the bottom of the widow is chose such that the specified % of the histogram area is below that poit. % of histogram hi trucated - the top of the widow is chose such that the specified % of the the histogram area is above that poit. Whe Apply is clicked, all ope images are updated. If Set defaults is checked whe Apply is clicked, the the settigs are saved as the future values applied whe images are opeed or Auto W/L executed. Oly certai discrete values are permitted for the parameters ad they are iterdepedet. Chagig oe parameter may chage others. Apply Recursive Filter The Tools Image Operatios Apply Rec Filter... commad is applicable for video sequeces ad applies a recursive filter. I this case each pixel value is replaced accordig to: Pix[i, ] = a*pix[i, -1] + b*pix[i,] Here the Pix[i,] is the i th pixel i the th frame. a is the Rec filter % expressed as a fractio ad b = 1 - a. The dialog box permits settig two values of the Rec filter % which are used accordig to whether movemet is detected or ot. Movemet o a arbitrary scale is calculated based upo pixel differeces ad compared to the user s threshold value. If the threshold is set to 200, the movemet detectio mechaism is tured off ad oly the Rec filter % i the top edit box is used. The routie performs a prelimiary calculatio to determie how may frames icorporate movemet ad the user is give a chace to adjust the threshold before the recursive filter is actually applied. Media Filter The Tools Image Operatios Media Filter commad results i the applicatio of a media filter to the selected image. Each pixel (except border pixels) is replaced by the media value of the set of 9 pixels a 3x3 kerel for which the pixel i questio is the ceter pixel PaxSca 3030CB / 4030CB Systems & Service Guide

95 This operatio occurs for the selected image ad the actual pixel values are modified. It is o-reversible, ad a image should be saved before performig this operatio if there is ay possibility the origial pixel iformatio may be eeded. Coe Beam Geerate Scaled Image The Tools Coe Beam Geerate Scaled Image fuctio is available whe the pixel data format of the selected image is 2MSBs are expoet. It operates o the pixel values i memory, ad caot be reversed. The result of the operatio is a image i which all pixel values are reduced by a factor of 2, ad the pixel data format is Usiged 16-bit. The Pixel Scale Factor is the idicated as 2 i the System tab of the Image Iformatio dialog. See extract from this dialog i the followig figure: Figure 6-40 Extract from Image Iformatio Dialog 6 Correct Image The Tools Coe Beam Correct Image fuctio is eabled whe the selected image was acquired usig a dual read or dyamic gai mode with all correctios tured off or Real-Time Video correctios disabled if it is a video sequece. The selected image will be corrected usig the existig calibratio provided: the image has ot bee saved ad re-opeed the acquisitio mode for the image is curretly selected the selected image is displayed i a image pae (ot a thumb pae) The curretly selected correctios will be applied. Real-Time Video Correctios The Tools Coe Beam Real-Time Video Correctios fuctio is checked by default. It results i correctios beig applied i real-time. If it is uchecked, correctios will ot be applied i real-time, ad correctios may optioally be applied after acquisitio is complete. This settig acts as a override of the correctios settigs. If post-acquisitio correctios is the preferred operatig mode the it is more coveiet to use this feature the cotiually tur correctios o/off i the System Settigs dialog. Computer systems vary ad it may ot be possible o a give system for correctios to be performed i real-time. Dyamic gai modes are particularly demadig of system resources, ad it is quite likely that real-time correctios will ot be possible whe a dyamic gai mode is selected. ViVA Help 6 95

96 6 96 PaxSca 3030CB / 4030CB Systems & Service Guide

97 Chapter 7 System Cofiguratio Importat: The followig iformatio details operatios which should oly be performed by experieced imagig persoel. Please cotact PaxSca Techical Support for more iformatio. I This Chapter Topic Page Cofigure Utility Applicatio 7-97 Usage 7-98 Mai Scree 7-99 Receptor Cofiguratio Settigs Mode Selectio Mode Setup Cofigure Utility Applicatio WARNING: Use of this applicatio program is strictly oly for the purpose of viewig the factory - istalled cofiguratio file settigs. Failure to do otherwise without prior permissio from Varia Medical Systems will void the Varia Medical Systems stadard warraty The purpose of the Cofigure Applicatio is to provide a iterface for buildig the ecessary cofiguratio files for the PaxSca Commad Processor. There are two required cofiguratio files, oe for system cofiguratio ad oe for receptor cofiguratio. The system cofiguratio file icludes iformatio that pertais to the etire system, such as the versio iformatio, etc. The receptor cofiguratio file icludes iformatio eeded to examie or if required correctly cofigure the receptor for acquisitio. Frame rate, biig, recursive filter percetage, etc. are examples of the data withi the receptor cofiguratio file. More specific iformatio about the data cotaied withi the cofiguratio files will be discussed later i this documet. 7 97

98 The Cofigure Applicatio is desiged to guide the user through a sequetial set of steps which will result i the successful creatio of a cofiguratio file. Thus, there are several dialog boxes which require iput such that cofiguratio file creatio will ot be completed util all the ecessary iformatio is provided. I geeral, for all dialog boxes, the data items which are gray are ot modifiable while all o-gray data items are modifiable. There are also several dialog boxes which caot be revisited i the same istace of the applicatio, i.e. oce OK is selected, the ability to retur to that widow may ot exist, so you will have to cacel ad restart the applicatio to chage that data. I geeral, if the Cacel butto of ay dialog box is selected, the cofiguratio file is ot cosidered complete. This Help documet is setup to guide the user through the sequetial usage of the Cofigure Applicatio; thus, the documet is ordered accordig to the appearace of the dialog boxes i the applicatio. Usage The first dialog box ecoutered determies how the Cofigure Applicatio will be used. The applicatio ca be used i customer mode, maufacturig mode or egieerig mode. This dialog box caot be revisited withi the same istace of the Cofigure Applicatio so the type of usage chose will be the same throughout that istace of the applicatio. The Usage dialog box ca be see below. Figure 7-1 Usage Dialog Box The purpose of the customer mode is to provide the ability to quickly create cofiguratio files for customers. The customer usage provides default values for all parameters. The maufacturig usage is desiged to custimize cofiguratio files for shipmet. Default values are ot provided i the maufacturig mode, istead, all cofiguratio iformatio must be etered by maufacturig based o the draft sheet or the cofiguratio file created i the field, usig the Customer Cofiguratio mode. The egieerig mode is desiged for experimetatio ad test purposes oly. Egieerig mode should oly be used by VIP egieers, others may use this mode at their ow peril. Egieerig mode will ot discussed withi this documet PaxSca 3030CB / 4030CB Systems & Service Guide

99 Mai Scree The purpose of the Mai Scree is to create a ew file or ope/edit a existig file ad/or save a file. The Mai Scree dialog box ca be viewed below. Figure 7-2 Mai Scree Dialog Box 7 The New... buttos will create a ew file. Selectig New... for System Cofiguratio will display the System Settigs dialog box. The Receptor Cofiguratio New... butto will display the Receptor Cofiguratio Settigs Dialog Box. Both of those dialog boxes will be discussed later. The Ope... buttos will display a Ope dialog box as show below. The Ope dialog box allows the user to ope files as i ay other applicatio, i.e. by double clickig o the file, or highlightig the file ad the selectig the Ope butto. If a file is opeed which is ot the correct format, default values will be used. Figure 7-3 Ope Dialog Box System Cofiguratio 7 99

100 The Save As... buttos behave like the Ope... buttos except the files will be saved to disk rather tha opeed. Existig files ca be overwritte, if Yes is selected whe asked if you wat to overwrite the existig file. The Edit... butto requires that data has bee etered either through opeig a existig file or through creatig a ew file. If a file has bee opeed with the Ope... butto, selectig the Edit... butto will result i the same dialog boxes, but the data will represet the data cotaied i the opeed file. Note that the File field is ot modifiable. This field will update to cotai the ame of the file which was most recetly opeed or most recetly saved. Receptor Cofiguratio Settigs The Receptor Cofiguratio Settigs dialog box (see below) allows the user to cofigure the receptor specific values for the receptor cofiguratio file. Figure 7-5 Receptor Cofiguratio Settigs The Receptor Cofiguratio Settigs dialog box allows the user to create modes which will cause mode specific dialog boxes to be displayed. Those dialog boxes will be discussed later. The dialog box will ot disappear util all required data is etered or Cacel is selected. The data items are defied i the followig table PaxSca 3030CB / 4030CB Systems & Service Guide

101 Table 7-2 Receptor Settigs Data Descriptio Data Item System Software Versio Receptor Serial Number Output Cofiguratio Max Pixel Value Descriptio The curret versio of software istalled o the system. The serial umber of the receptor, as etered by Maufacturig. Defies the 16-bit video output as LVDS. Defies 12-bit or 14-bit data acquisitio mode. Correctios: The correctios allow the user to defie how the system correctios are cofigured for system start-up. Offset Calibratio Gai Calibratio Whether or ot offset correctios are eabled at system start-up. Whether or ot gai correctios are eabled at system start-up. Pixel Correctios BLC Receptor Type Mode Settigs Whether or ot pixel correctios are eabled at system start-up. Whether or ot black level clampig (BLC) is eabled at system start-up. The type of receptor istalled with the system. Allows the user to defie the modes for the system. 7 Isert... This butto allows the user to isert a ew mode. This butto serves as the add ad isert fuctio. If o row i the table is selected the ew mode will be stored i the ext available slot. If a row is selected, the ew mode will be iserted above the selected row. Modes ca be added util the maximum umber of modes is reached. This umber is based o the size ad umber of modes created. Edit... This butto allows the user to edit a mode. To edit a mode, select the row i the table which correspods to the mode that eeds to be edited. If o modes exist (i.e. through the Isert commad or a file ope operatio), a error will be displayed. Delete... This butto allows the user to delete a mode. To delete a mode, select the row i the table which correspods to the mode that eeds to be deleted. System Cofiguratio 7 101

102 Table 7-2 Receptor Settigs Data Descriptio Data Item Descriptio Up Arrow This butto allows the user to move a mode to a higher positio i the list. To move a mode, select the row of the desired mode, the select the up arrow. The selected mode will be moved oe row higher i the table uless the mode is o the first row. Dow Arrow This butto allows the user to move a mode to a lower positio i the list. To move a mode, select the row of the desired mode, the select the dow arrow. The selected mode will be moved oe row lower i the table uless the mode is o the last row. The Receptor Type must be selected before eablig a mode. If ot, a message box will appear istructig the user to select a Receptor Type before cotiuig. Please ote that if a mode is ot completely cofigured, i.e. the Cacel butto o oe of the mode cofiguratio dialog boxes is selected durig creatio of the mode (i.e. while performig a New operatio), the mode will be deleted i the Receptor Cofiguratio Settigs dialog box. Mode Selectio The Mode Selectio Dialog Box allows the user to choose the mode type. Whe Isert... is selected, if the receptor has the DCDS feature, the followig dialog box will appear to allow the user to select the lie legth desired. Figure 7-6 DCDS Lie Legth Dialog Box The mode types will vary depedig o the receptor type ad lie legth as appropriate. Oce a mode type is selected, the Mode Setup dialog box will be displayed. The followig dialog box is a example of the Mode Selectio dialog box PaxSca 3030CB / 4030CB Systems & Service Guide

103 Figure 7-7 Mode Selectio Dialog Box The gray box at the top left is ot modifiable ad oly provides a remider as to which mode the user has eabled. Mode Setup The Mode Setup dialog box allows the user to select specific details that pertai to how the system should cofigure a particular mode. The data that appears i the Mode Setup dialog box will deped o the type of mode selected, the receptor type ad the lie legth as appropriate. The followig dialog box is a example of the Mode Setup dialog box. 7 Figure 7-8 Mode Setup Dialog Box The followig table describes the data items i the Mode Setup dialog box. System Cofiguratio 7 103

104 Data Item Table 7-3 Mode Selectios Descriptio Mode # Mode Name Receptor Type DCDS Eable Frame Rate Gai Biig Frame Sychroizatio Calibratio Iformatio: Number of the selected mode. Iformatio oly, ot modifiable. A high level descriptio of the mode type that has bee selected for cofigurig. Iformatio oly, ot modifiable. The type of receptor that was selected. Iformatio oly, ot modifiable. Whether or ot DCDS correctios are eabled for the mode selected. Iformatio oly, ot modifiable. The frame rate for the mode. The gai value applied to sigals before digital-to-aalog coversio. The umber of receptor pixels which are bied to make oe image pixel. Defies how frames will be sychroized. Free Ruig - The frame start syc pulse ad all iteral clocks are created from iteral circuits. Lie Syc - The frame start pulse ad iteral clocks are geerated iterally, but the AC lie frequecy is used as a referece. This optio is ot available for certai mode/receptor combiatios. User Syc - Frame start pulse is supplied from the user, all itteral clocks are the geerated based o the user supplied frame start pulse. Iformatio for how a calibratio should be performed. Number of Calibratio Frames The umber of frames to accumulate durig a calibratio. Offset Threshold Value for Defects Gai Scalig Threshold value used durig offset calibratios to boud values. If Disable is selected, gai scalig will be off, else if eable is selected, gai scalig will be o. Auto Calibratio Iformatio: Auto offset calibratio data, eabled or disabled. If disabled, the other data does ot eed to be etered. Mi Delay Post-Exposure Delay The miimum time delay betwee auto-offset calibratios. The amout of time delay required after a exposure PaxSca 3030CB / 4030CB Systems & Service Guide

105 Table 7-3 Mode Selectios Data Item Pixel Iformatio: Recursive Filter Pixel Saturatio Threshold Value Pixel Saturatio Replacemet Value Descriptio Iformatio pertaiig to how pixels will be rouded. The fractioal cotributio to each output frame by the data already i the recursive filter buffer. The value at which a pixel is cosidered to be saturated. The value with which to replace a pixel that is determied to be saturated. System Cofiguratio: Hostdow Utility Applicatio Updates via Serial Lik The Hostdow Utility Applicatio is used for ay software program update, chage or revisio. The system cofiguratio software package used to cofigure the PaxSca 3030CB / 4030CB Commad Processor cosists of the followig: 7 Table 7-4 System Cofiguratio Software Package Files Fileame System Software Global Cotrol Firmware 3030CB / 4030CB Receptor Firmware Receptor Cofig Data Descriptio Embedded operatig system, which rus o the motherboard ad cotrols the operatio ad iterfacig of all other Commad Processor hardware. Firmware which programs FPGAs o the Global Cotrol Board. Firmware which programs FPGAs o the digital board i the Receptor. Cofiguratio file which defies the modes of operatio for the Receptor. Hostdow Target Commads Oce Hostdow has made a coectio to the Commad Processor, oe of two basic fuctios ca be performed: The IP address of the Commad Processor ca be chaged by choosig Chage Target s IP Address from the Target Commads meu. Dowloadig of system software, firmware files, ad ca be doe by selectig Dowload to Target from the Target Commads meu. System Cofiguratio 7 105

106 Usig the Dowload to Target commad, the user ca maually dowload ay oe of these files, or use the Automated Dowload feature to dowload all the required files. Hostdow is also desiged to support batch file dowloadig usig the Auto Dowload File Set feature show i Figure There are several types of cofiguratio files which reside permaetly i the flash memory of the Commad Processor. The files listed above ca be replaced by dowloadig ew versios over a serial lik usig the utility applicatio hostdow.exe, by followig these ext steps. 1. Power Off the Commad Processor. 2. Coect your computer COM port to the Commad Processor s serial 1 port. 3. O cliet computer, ru the Hostdow.exe program located i the commad_processor directory i the PaxSca 3030CB / 4030CB Software release folder. 4. Click Hostdow. The followig scree appears: Figure 7-9 Hostdow Mai Scree 5. From the meu bar choose Cofigure->Commuicatios Port->COM X. COMX should be ay free COM port o the cliet computer. 6. Click Coect. The followig widow will appear: 7. Oce this widow appears, tur Commad Processor power O. The followig widow will ope whe a coectio is established: PaxSca 3030CB / 4030CB Systems & Service Guide

107 8. Click Ok.The followig widow appears: 9. From the meu choose Target Commad->Dowload To Target... The followig scree appears: Figure 7-10 Auto Dowload File Set Click o the active pull-dow meu to select AutoDowload Set for 3030CB / 4030CB Receptors. 11. Whe dowload is complete, exit Hostdow ad restart the Commad Processor. Allow the Commad Processor to boot-up completely, the cycle power ad allow the Commad Processor to boot-up agai. The Commad Processor must be reset twice i order for the firmware to be loaded properly. System Cofiguratio 7 107

108 System Cofiguratio: ViVA Applicatio While the Hostdow Utility applicatio may be used for ay software upgrade, the ViVA applicatio allows upgrades without power cyclig the Commad Processor. ViVA may be used as a egieerig tool to modify small subsets of software files, or to chage the Receptor mode cofiguratio from 15 to 30 frames per secod for example. It is simply a matter of coveiece. With the Hostdow Utility applicatio, you must power dow the Commad Processor, ad power back up. However, for ViVA to work properly the system must fully boot for ViVA to establish commuicatio. If the Commad Processor does t boot, the Hostdow must be used to dowload ay files to flash. Upgrades over the Etheret Coectio The Commad Processor uses flash memory to store various cofiguratio files. Some of these files ca be updated through the ViVA software over the Etheret coectio. The followig files ca be updated over the Etheret Lik: Receptor Cofiguratio Data File Base Defect Image File (Defective Pixel Map) Gai Calibratio File Offset Calibratio File Firmware Files Cofiguratio Files The basic procedure for performig the update is very similar for each file. This example illustrates how to dowload the Base Defect Image File. 1. Coect to the Commad Processor with ViVA 2. From the ViVA meu bar, select Tools>CommadProcessor>Trasmit Files. The followig widow will ope: PaxSca 3030CB / 4030CB Systems & Service Guide

109 Figure 7-11 ViVA Trasmit Files Selectio 7 3. Select a file for dowload by clickig o the checkbox ext to the file descriptio. 4. Click the Browse butto ad select the ew defect map file. This file is provided o the CD-ROM shipped with the Receptor. The file will be labeled with a fileame that correspods to the mode it was geerated i. 5. I the secod field, select a mode that correspods to the mode-specific defect map to be dowloaded. Click OK to trasmit the file. The Trasmit Files widow will close ad ViVA will trasmit the defect map to the Commad Processor flash memory. The defect map for each mode must be trasmitted oe at a time. 6. Steps 2-5 may be repeated for all modes loaded i the Commad Processor flash memory. The Receptor cofiguratio data file determies the umbers of modes loaded ito memory. There is a customized defective pixel map associated with each mode loaded i memory. This meas that a defective pixel map should be updated aytime a Receptor cofiguratio data file is updated. System Cofiguratio 7 109

110 7 110 PaxSca 3030CB / 4030CB Systems & Service Guide

111 Chapter 8 Commad Processor Hardware Specificatios This sectio outlies the hardware specificatios eeded to operate the PaxSca 3030CB / 4030CB imagig system. I This Chapter Topic Page Hardware Compoets Commad Processor Hardware Cofiguratio Pulsed X-ray Beam Applicatios Iteral Power Supply Specificatios Commad Processor Specificatios Hardware Compoets 8 The PaxSca 3030CB / 4030CB digital imagig system cosists of the followig compoets: Receptor Commad Processor exteral sychroizatio 16-bit video Fiber Optic Lik (Receptor) 8 111

112 Commad Processor Hardware Cofiguratio Motherboard The Motherboard is a MIPS-based computer. The Motherboard cotais flash memory ito which the system software is loaded. The system software cotais the operatig system ad the software program resposible for the cotrol ad commuicatio of all Commad Processor hardware. Figure 8-2 Commad Processor Hardware Itercoectio The operatioal modes of the Receptor are also stored i flash memory. The Receptor Cofiguratio file defies the operatioal modes of the Receptor. The Receptor Cofiguratio file ca be created with the Cofiguratio applicatio. IPCU The IPCU card receives high speed serial data from the Receptor. The data is re-framed ad passed to the IPU for image processig. The IPCU card outputs a LVDS 16-bit digital video sigal. The IPCU card receives power from the iteral Power Supply lik ad passively filters all supply voltages, which are distributed to the Motherboard, IPU, ad to the Receptor. The IPCU card provides customer iterfacig through a exteral sychroizatio port, capable of hadlig both iput ad output. The specificatios for this port are outlied i the System Overview chapter of this guide. The image processig uit (IPU) is resposible for real-time image processig o the raw data received from the Global Cotrol card. Exteral Sychroizatio: Hardware Hadshakig The Exteral Sychroizatio port provides mode cotrol ad verificatio o a frame-by-frame basis. The default hadshakig protocol outlied i Table 8-3, is used primarily to verify that the PaxSca 3030CB / 4030CB is fuctioal, ad that valid data are beig output. This port is used to iput hardware sigals that iitiate frame acquisitios. All I/O o this port is performed through opto-couplers. Each sigal is set or received as a differetial pair. The geeral cocept of the opto-coupler iterface is illustrated i Figure PaxSca 3030CB / 4030CB Systems & Service Guide

113 Figure 8-3 Geeric Opto-Coupler Iterface The output pulls the sigal lie low with a ope collector driver. The receiver side must provide a additioal resistor to limit the curret. The grouds of the two systems are ot coected, ad the iterface should operate correctly for large commo mode differeces. The pi assigmets for the exteral sychroizatio port are show i Table 8-1. Table 8-1 Pi Assigmets of the Exteral Sychroizatio Port 8 Pi # Assigmet Pi # Assigmet 1 OptPOut[0] 26 OptPI[0] 2 OptMOut[0] 27 OptMI[0] 3 OptPOut[1] 28 OptPI[1] 4 OptMOut[1] 29 OptMI[1] 5 OptPOut[2] 30 OptPI[2] 6 OptMOut[2] 31 OptMI[2] 7 OptPOut[3] 32 OptPI[3] 8 OptMOut[3] 33 OptMI[3] 9 OptPOut[4] 34 OptPI[4] 10 OptMOut[4] 35 OptMI[4] 11 OptPOut[5] 36 OptPI[5] 12 OptMOut[5] 37 OptMI[5] 13 OptPOut[6] 38 OptPI[6] 14 OptMOut[6] 39 OptMI[6] 15 OptPOut[7] 40 OptPI[7] 16 OptMOut[7] 41 OptMI[7] 17 GND 42 OptPI[8] 18 OptPOut[8] 43 OptMI[8] Commad Processor Hardware Specificatios 8 113

114 Table 8-1 Pi Assigmets of the Exteral Sychroizatio Port Pi # Assigmet Pi # Assigmet 19 OptMOut8] 44 OptPI[9] 20 OptPOut[9] 45 OptMI[9] 21 OptMOut[9] 46 OptPI[10] 22 OptPOut[10] 47 OptMI[10] 23 OptMOut[10] 48 OptPI[11] 24 OptPOut[11] 49 OptMI[11] 25 OptMOut[11] 50 GND Pis 1 25 are outputs, pis are iputs, ad shield is at GND. The coector is a 50 pi D-submiiature, AMP Table 8-2 Default Hardware Hadshakig Iterface Sigal Assigmet Pi # Prepare OptPI[0] 26 OptMI[0] 27 Valid_Xray OptPi[1] 28 OptMi[1] 29 Valid_Frame OptPOut[0] 1 OptMOut[0] 2 Pael_Ready OptPOut[2] 5 OptMOut[2] 6 Reset OptPI[2] 30 ot curretly implemeted OptMI[2] 31 Radiatio_Warig OptPI[3] 32 ot curretly implemeted OptMI[3] 33 Pael_Healthy OptPOut[3] 7 OptMOut[3] 8 Mode_Cotrol_Bit0 OptPI[4] 34 ot curretly OptMI[4] 35 implemeted PaxSca 3030CB / 4030CB Systems & Service Guide

115 Table 8-2 Default Hardware Hadshakig Iterface Sigal Assigmet Pi # Mode_Cotrol_Bit1 OptPI[5] 36 ot curretly implemeted OptMI[5] 37 Mode_Cotrol_Bit2 OptPI[6] 38 OptMI[6] 39 User_Vsyc OptPI[11] 48 OptMI[11] 49 Valid_RAD_Frame OptPOut[5] 11 ot curretly implemeted OptMOut[5] 12 Expose_Ok OptPOut[4] 9 OptMOut[4] 10 Table 8-3 Default Hardware Hadshakig Sigals 8 Evet Causig Iterrupt Prepare Iterpretatio Sigal from the OEM Cotroller. Prepare = True idicates that productio of X-rays is immiet. Prepare = False idicates that productio of X-rays is o loger immiet. PaelReady Sigal from the PaxSca 3030CB / 4030CB. Prepare = True idicates a exposure is about to begi. PaxSca 3030CB / 4030CBshould respod with PaelReady = True withi three frames. PaelReady = False after three frames idicates a error coditio. ValidXRays Sigal from the OEM Cotroller. Idicates X-rays are at the proper itesity. This sigal is asychroous. ValidXRays = True idicates that X-rays have begu to be produced at the iteded X-ray itesity. ValidXRays = False idicates that X-rays are o loger beig produced at the iteded itesity. Commad Processor Hardware Specificatios 8 115

116 Table 8-3 Default Hardware Hadshakig Sigals Evet Causig Iterrupt PaelHealthy Iterpretatio A sigal from the PaxSca 3030CB / 4030CB. PaelHealthy = True idicates ormal fuctioig. This sigal should be true withi 30 secods after startup. ValidRADFrame ot curretly implemeted Sigal from the PaxSca 3030CB / 4030CB. ValidRADFrame = True idicates the radiographic acquisitio has bee fully processed ad is curretly beig displayed o the 16-bit video port. Expose_Ok A active low sigal from the PaxSca 3030CB / 4030CB. Expose_Ok = True otifies the OEM X-ray geerator it is safe to deliver pulsed X-rays. ValidFrame Idicates the precedig frame has bee fully exposed. If a frame, N, has bee read by the PaxSca 3030CB / 4030CB, where ValidXrays = True durig the etire precedig frame period, N-1, as well as durig the etire period i which the frame was read, the the PaxSca 3030CB / 4030CB will tag this frame as fully exposed with ValidFrame = True. If a frame is fully exposed, ValidFrame will be True durig the first Vblak succeedig this frame. If a frame is oly partially exposed, or ot exposed at all, ValidFrame will be False durig the first Vblak succeedig this frame. Due to the ature of the flat pael, a frame must be exposed to valid X-rays for at least two frame periods, ad read out durig the secod frame period, i order to be a fully exposed frame (oe capable of beig tagged with the ValidFrame = True sigal) The ValidFrame sigal will ot toggle durig the Vblak period. The PaxSca 3030CB / 4030CB will stay i active fluoroscopic mode as log as Prepare = True, idepedet of the ValidXray/ ValidFrame sigals PaxSca 3030CB / 4030CB Systems & Service Guide

117 16-bit Video Output Sigals The video bus cosists of twety sigals, described i Table 8-4. Table 8-4 Video Iterface Sigals Sigal Name Number of Sigals Descriptio PixClk 1 Pixel Clock: All sigals are sampled o the risig edge of this clock. Vsyc 1 Vertical Syc: Fallig edge of this sigal defies the begiig of a video frame. Hsyc 1 Horizotal Syc: Fallig edge of this sigal defies the begiig of a video lie. Dvalid 1 Data Valid: Low level of this sigal implies image data is valid. Data[15:0] 16 Data: Cotais up to sixtee bits of data. Logic Levels All sigals are defied as LVDS (low voltage differetial sigalig). Each idividual sigal cotais a positive ad a egative compoet. Thus, the twety sigals actually require forty coectios. The recommeded LVDS receivers are show i the followig tables. 8 The sigals are traslated from CMOS/TTL levels, ad are trasmitted usig LVDS. Table 8-5 Typical LVDS Levels Iput Voltage 0V < receiver iput voltage < 2.9V Differetial Iput Threshold High Differetial Iput Threshold Low Iput Curret +100 mv (maximum) -100 mv (miimum) -20 µa (miimum), +/- 1 µa (typical), +20 µa (maximum) Commad Processor Hardware Specificatios 8 117

118 Table 8-6 Recommeded LVDS Parts Part Number Descriptio Maufacturer DS90C031TM DS90C032TM DS92LV010A LVDS Quad CMOS Differetial Lie Drive LVDS Quad CMOS Differetial Lie Receiver Bus LVDS 3.3/5.0V Sigle Trasceiver Natioal Semicoductor Natioal Semicoductor Natioal Semicoductor Frame Timig A video frame cosists of a real data frame iside of a virtual frame. The virtual frame is icreased from the real data frame by four strips of blakig: top vertical, bottom vertical, left horizotal ad right horizotal, as illustrated below. Figure 8-4 Frame Timig Blakig allows time for processig ad other delays. Historically, at VIP the top vertical ad left horizotal blakig are much smaller tha the bottom vertical ad right horizotal blakig. This is at preset opposite to the idustry orm. Vsyc ad Hsyc defie the vertical ad horizotal edges of the virtual frame. The miimum size for ay blakig is four pixels PaxSca 3030CB / 4030CB Systems & Service Guide

119 Table 8-7 PixClk Timig Specificatios Model Mi Max Uits T clk s F clk = 1/t clk MHz T clk jitter (pp) 2 s T clk duty cycle % T high 12.5 s T low 12.5 s Sigal: Vsyc Vsyc defies the begiig of the frame. Vsyc goes low at the upper left corer of the virtual frame ad stays low for two to eight lies. It the returs high util the ext frame. Vsyc must go low durig the same clock cycle that Hsyc goes low. Figure 8-5 Vsyc Timig Diagram 8 Table 8-8 Vsyc/Hsyc/Data Valid Timig Specificatios Model Mi Max Uits T s 2.5 s T h 1.5 s T valid 2 8 lies Data Valid must remai high durig the valid image data frame. Thus, burstig of data with gaps are ot allowed.t valid, oted above, is ot applicable to Data Valid. Commad Processor Hardware Specificatios 8 119

120 Sigal: Hsyc Hsyc defies the begiig of a lie. Hsyc goes low at the left edge of the virtual frame ad stays low for two to eight pixels. It the returs high util the ext frame. The timig for Hsyc is equivalet to the timig for Vsyc. Sigal: DataValid DataValid defies the real image data withi the virtual frame. DataValid is high durig blakig, ad low whe valid image data is preset o the data lies, which icludes the black level clampig data. The timig figure for DataValid is equivalet to the diagram for Vsyc ad Hsyc. DataValid must be low cotiuously durig the valid image data frame. Thus, burstig of data with gaps are ot allowed. 3030CB / 4030CB UserSyc Fluoroscopy Video Timig Figure 8-6 User Syc Fluoro Overall Timig Figure 8-7 Detailed View of oe HSYNC ad Data Valid PaxSca 3030CB / 4030CB Systems & Service Guide

121 3030CB / 4030CB Full Resolutio, Full Field Video Timig Figure 8-8 Full Resolutio Overall Video Timig with User Syc Figure 8-9 Full Resolutio Detailed Video Timig 8 Coector ad Cable Piouts Presetly, two coector piouts ad cables are supported. The piout for the supported coectors are show i Figure Commad Processor Hardware Specificatios 8 121

122 Figure 8-10 LVDS ad CameraLik Coector Pi Assigmets LVDS CameraLik LVDS The coectors at both the trasmitter ad the receiver are AMP 50pi SCSI-II receptacles, right-agle or vertical. The cable is a stadard 50 coductor SCSI-II cable with male plugs at both eds. The piout for the coectors is show i Figure Recommeded: L-COM SCSI-2 Cable #CA801-XM, where X is legth. MOUT refers to the mius data out ad POUT refers to the plus data out. Grouds are iteral grouds, ot case grouds. They are to be tied at the trasmitter oly. CameraLik The coectors at both trasmitter ad receiver are stadard camera lik coector from 3M. It is a.050" surface mout right agle, 26-pi coector with part umber A10VE. The cable is a stadard camera lik cable from 3M with part umber 14X26-SZLB-XXX-0LC, where the first X is shell retetio optio, ad the 3 X's are legth i meters (please refer to Camera Lik Specificatios for more details). The pi out for the coectors is show i figure PaxSca 3030CB / 4030CB Systems & Service Guide

123 User Sychroizatio Mode This mode allows users utilizig Exteral Sychroizatio 50 pi D-Sub coector, to itroduce the Frame Start sigal. The sigal is itroduced o pis OptPI[11] ad OptMI[11] of the Exteral Sychroizatio port. Whe operatig User Syc mode, the User Syc sigal bypasses the DPLL module i the Commad Processor. Although the User Syc bypasses the DPLL module, it is received by digital logic which igores additioal triggers util the ed of the video data output, i.e. the ed the Real Frame. However, glitches o the User Syc lie should be avoided sice they could accidetally trigger the pael before the ed of the Virtual Frame, causig the pael to see a frame rate potetially higher tha the allowed maximum. Timig The Commad Processor will lock the geeratio of all iteral clocks to the risig edge of the User Sychroizatio sigal provided by the user. Assumig the PaxSca imager is usig the maximum readout rate, which is approximately 40 usec/lie, the frequecy requiremets for the User Syc are: Fluoro Mode < 30Hz; Full-Resolutio Mode < 7.5 Hz. For slower lie rates, the maximum User Syc frequecy is reduced. Mode Table 8-9 Frame Rate vs. Vertical Blak Time Biig Matrix Frame Rate /Vblak Name Row/Colum Row/Colum [max]/[ms] 8 If low oise ormal 2/2 1024/768 30/1.34 fluoro Ifr low oise full 1/1 2048/ /30 resolutio fluoro Termiatio Scheme ad Loadig The recommeded termiatio scheme is show i Figures The recommeded LVDS drivers ad receivers i Table 8-6 do ot iclude termiatios iside the LVDS package. Figure 8-11 LVDS Sigal Termiatio Scheme 100Ω Commad Processor Hardware Specificatios 8 123

124 Pulsed X-ray Beam Applicatios Timig Iformatio Asychroous X-ray exposure ca cause additioal oise ad iterferece appearig as stripes of differet brightess, which occur at poits throughout the image correspodig to the beam ON times. To avoid this iterferece, X-ray beam sychroizatio is used. A frame is composed of a pael readout period ad a vertical blakig period. The X-ray pulses must be delivered withi the vertical blakig period i order to prevet image artifacts. The Commad Processor Expose_OK output otifies the X-ray geerator whe it is safe to deliver the X-ray beam. The sigal is available o the Exteral Sychroizatio port. The Expose_OK is egative durig the vertical blakig iterval, which is the portio of the frame time after the readout (scaig) is complete. I order to prevet the stripe artifact i the image, the X-ray beam should oly be o whe Expose_OK is egative. The Expose_OK sigal is coected to the OptMOut(4) pi of the Exteral Sychroizatio port. The OptPout(4) pi of the same port is coected to +5 Power Supply VCC. These outputs are to be coected to a opto-coupler, such as a HCPL063 from Hewlett Packard. Figure 8-13 Timig for Systems with Pulsed X-ray Beam Delivery Iteral Power Supply Specificatios The iteral Two-Output Power Supply (TOPS) has bee desiged for use i Varia's imagig products. It is a UL approved two-output power supply. There is a 5V output with remote sese used to iterally power the Commad Processor ad a 24V supply used to exterally power the Receptor PaxSca 3030CB / 4030CB Systems & Service Guide

125 Table 8-10 Iteral Power Supply Specificatios Commad Processor Iput Supply Voltage Outputs Specificatio Vac, 47-63Hz sigle phase Receptor: 24V / 3A omial, 5A maximum Cotrol ad Moitorig Commad Processor O/Off Switch: A power switch, located at the rear of the commad processor, will coect/discoect AC power to the uit. The power switch is a DPST pael mouted rocker switch, which makes & breaks both AC lies. O/Off Idicators: A gree LED at the frot of the commad processor will idicate that AC power is applied to the uit ad the power switch is i its o postio. Mechaical Specificatios Figure 8-14 Receptor 8 Commad Processor Hardware Specificatios 8 125

126 Figure 8-15 Commad Processor Commad Processor Specificatios Serial Iterfaces Two serial ports are provided. These are implemeted with two male 9-pi D-type coectors. Their pi defiitios are: Table 8-11 Serial Port Oe (P1) Sigal Name Pi # Sigal Name Pi # 1 DTR 6 TXDA 2 CTS 7 RXDA 3 RTS GND PaxSca 3030CB / 4030CB Systems & Service Guide

127 Table 8-12 Serial Port Two (P2) Sigal Name Pi # Sigal Name Pi # 1 6 TXDB 2 7 RXDB GND 5 Etheret Port The Etheret port shall iterface through a 8-pi right agle RJ-45 coector (P3). It shall have the pi-out listed below: Table 8-13 Etheret Coector (P3) Sigal Name Pi # Sigal Name Pi # TxD+ 1 GND 5 TxD- 2 RxD- 6 RxD Commad Processor Hardware Specificatios 8 127

128 8 128 PaxSca 3030CB / 4030CB Systems & Service Guide

129 Chapter 9 Safety Receptor Module WARNING: Precautios should be take to ot ope the receptor module. Depedig upo the type of scitillator used, opeig the receptor module may expose the user to potetially toxic materials. Receptor Moutig The Receptor should be mouted oto other pieces of equipmet usig the holes provided i the itegral flage. WARNING: The Receptor has a optioal lead cap which ca be used as a primary barrier to X-rays. This barrier is oly effective if the X-ray beam is collimated i such a way that X-rays impige o the active surface of the Receptor. 9 WARNING: If the Receptor is to be used as a primary barrier to X-rays, the X-rays must impige o oly the etrace widow of the Receptor. The optioal lead cap will ot stop X-rays that do ot hit the etrace widow of the receptor. CAUTION: The frot surface of the Receptor is desiged to be splash-proof, but the electrical coector at the backside of the Receptor is ot sealed agaist moisture

130 Commad Processor Rack Moutig the Commad Processor The Commad Processor ca be rack mouted i a stadard 3U (5.2" high) slot usig optioal rack moutig iteded for a 19" wide rack. Optioal slidig brackets are also available. CAUTION: The followig precautios should be observed whe rack moutig the Commad Processor: Elevated operatig ambiet temperature: If istalled i a closed or multi-uit rack assembly, the operatig ambiet temperature of the rack eviromet may be greater tha room ambiet. Equipmet should be istalled i a eviromet compatible with the maximum rated ambiet temperature. Reduced air flow: Istall the equipmet so that the amout of air flow required for safe operatio is ot compromised. Mechaical loadig: Moutig of the equipmet i the rack should be loaded evely to avoid ay hazardous coditios. Circuit overload: Cosideratio should be give to the coectio to avoid overloadig of circuits o the over-curret protectio ad supply wirig. Reliable groudig: Reliable groudig should be maitaied, with particular attetio give to the supply groud coectio. Evirometal Coditios Table 9-1 Evirometal Coditios Storage/Shippig Temperature Storage/Shippig Humidity Full-spec Operatig Temperature (Measured at the ceter of the back cover.) -20 C to +70 C 10% to 90%, o-codesig 10 to 35 C Operatig Humidity (o-codesig) 10 to 90% PaxSca 3030CB / 4030CB Systems & Service Guide

131 Coolig Requiremets Importat: The back surface temperature of the Receptor should ot exceed 35ºC whe the uit is istalled. This requiremet may ecessitate air flow over the back surface of the Receptor. Importat: Ambiet air temperature should ot exceed 40ºC for the Commad Processor. Importat: The Commad Processor do ot have air filters, so the air should be free of dust ad particulates. Importat: Coolig air clearace requiremets for the Commad Processor are four iches miimum from each surface. WARNING: The uit must comply with those stadards listed uder each category to the levels detailed. Assume the most striget requiremets prescribed by the stadard if o levels are detailed. 9 WARNING: The PaxSca 3030CB / 4030CB is ot classified for use i the presece of a flammable aaesthetic mixture with air, or with oxyge or itrous oxide. CAUTION: The uit must comply with those stadards listed uder each category to the levels detailed. If o levels are detailed, assume the most striget requiremets prescribed by the stadard. Safety 9 131

132 Electro-Magetic Compatibility Uder ormal operatig coditios, the imager will comply with IEC Refereced Stadard IEC EN EN EN EN EN EN EN EN Class A Required +/- 6kV Cotact, +/- 8kV Air 80MHz-2.5GHz@3V/m +/-1kV@ I/O Cable, +/- PS +/-1kV DiffMode, +/-2kV ComMode 150kHz - 3Vrms Required Electro-Magetic Iterferece This equipmet geerates, uses ad ca radiate radio frequecy eergy ad, if ot istalled ad used i accordace with the istructios, may cause harmful iterferece to other devices i the viciity. However, there is o guaratee that iterferece will ot occur i a particular istallatio. If this equipmet does cause harmful iterferece to other devices, which ca be determied by turig the equipmet off ad o, the user is ecouraged to try to correct the iterferece by oe or more of the followig measures listed i the Troubleshootig sectio. Electrical Shock protectio Class 1 Equipmet per UL X-Ray Leakage with Pb barrier Uder ormal operatig coditios, o damage, ad X-rays icidet oly o the active area: IEC PaxSca 3030CB / 4030CB Systems & Service Guide

133 Safety Agecy Approvals The imager willl comply with all of the followig safety agecy stadards ad be appropriately labeled: US: UL Caada: CSA 22.2 No M90. Europe: IEC CE marked. 9 Safety 9 133

134 9 134 PaxSca 3030CB / 4030CB Systems & Service Guide

135 Chapter 10 Maiteace Prevetative Maiteace CAUTION: Substitutio for ay of the PaxSca compoets with uits of a differet type may cause catastrophic damage to the PaxSca imagig system, ad will degrade the miimum safety of the PaxSca 3030CB / 4030CB. No special prevetative maiteace is required; however, prudet ispectios should be carried out to check for: Damaged ad wor cables Sigs of severe shock to the Receptor, lead cap, Commad Processor Evidece that fas are clear ad ruig Calibratio Schedule Offset calibratio is performed automatically durig times whe X-rays are ot impigig o the Receptor. Gai calibratio eeds to be performed with the assistace of a operator at regular itervals. If the Offset calibratio is cotrolled by the user, it should be performed as ofte as possible. It is recommeded that Gai calibratio be doe at least mothly, ad more ofte if image quality degradatio is observed. Durig Gai calibratio, the map of defective pixels is also updated. 10 Receptor Module WARNING: Precautios should be take to ot ope the receptor module. Depedig upo the type of scitillator used, opeig the receptor module may expose the user to potetially toxic materials. Maiteace

136 Repairs No user serviceable parts. If repairs are ecessary, please cotact the Varia Imagig Products Service Ceter at , or The IEC receptacle fuses o the Commad Processor are replaceable by Varia service persoel. These fuses are idetified by a label ear the IEC receptacle, ad must be replaced with the exact size ad type called out o the label. The least replaceable uits (LRU) are: Receptor Assembly Commad Processor Assembly Receptor Power Cable Receptor Fiber Optic Cable Commad Processor Power Cable Cleaig, Disifectio ad Sterilizatio The Receptor is the oly compoet that is likely to be i the area of a patiet. Although this compoet is ot iteded to come i cotact with the patiet, it is possible for the patiet or user to touch the Receptor face. The material most likely to come i cotact with the patiet is X-ray grade carbo fiber i a cast alumium frame. The Receptor is ot sealed agaist moisture. Cleaig, disifectio ad sterilizatio of the iput widow should be accomplished as eeded, but cleaig of the iput widow should be accomplished at a miimum of oe moth itervals. Proper disifectio ad sterilizatio requires that a disifectat/sterilizatio solutio be used. Wipig the surfaces with a soft cloth dampeed with soap ad water will geerally clea the surfaces PaxSca 3030CB / 4030CB Systems & Service Guide

137 Chapter 11 Troubleshootig HyperTermial HyperTermial is a program, supplied by Microsoft, that iterfaces to the serial port 1 o the Commad Processor. HyperTermial is used to moitor status ad debug messages outputted from the Software ruig i the commad processor. The Commad Processor will display status ad debug messages oly o boot-up. After boot-up has bee completed, debug messages are tured off to icrease system performace. Figure 11-1 HyperTermial Widow To eable debug messages durig rutime select Tools>Commad Processor>Debug Verbosity from the ViVA pull dow meu. Figure 11-2 ViVA Widow 11 Makig these messages available to Techical Support will be very helpful i diagosig ay potetial problems with the PaxSca system. To capture the debug messages to file select Trasfer>Capture Text

138 The eter a path ad fileame. The COM port should be cofigured as follows: Figure 11-3 Com Port Cofiguratio HyperTermial must be closed whe attemptig to use Hostdow. This is because both programs access the same COM port for commuicatio with the Commad Processor PaxSca 3030CB / 4030CB Systems & Service Guide

139 Problems ad Solutios Problem Imager fails to respod. Table 11-1 Troubleshootig Solutio 1. Check the power ad the Restart. 2. Check fuse ad cables. Imager causes Electro-Magetic Iterferece 1.Reoriet or relocate the receivig device. 2.Icrease the separatio betwee the equipmet. 3.Coect the equipmet ito a outlet o a curcuit differet from that to which the other device (s) are coected. 4. Cosult the maufacturer or field service techicia for help. Bad Pixel Correctio fails. 1. Repeat measuremet. 2. Re-acquire gai ad offset images. 3. Assure that the acquired Light ad MidField images fill the field of view ad that the exposures are appropriate for Light ad MidField images. Software hags up. Make sure the Power Supply module is switched O ad the data cable to the PC is properly coected. If Exteral Frame time was selected, make sure the iput sigal is geerated. Acquired image is completely dark. Out of virtual memory. Icrease the frame time ad acquire a ew image. If the image is still dark, verify that the cables from the Power Supply to the Receptor, ad from the Receptor to the computer are properly coected. Tur the power Off ad O. Acquire a ew image. Close some of the widows that are curretly ope. 11 Residual X-ray image from previous sca shows i curret sca. Charge o the sesor pixels from a super saturated exposure may cause a residual image. It ca be erased by takig a sca or multiple scas without X-rays util the residual image is goe. Troubleshootig

140 PaxSca 3030CB / 4030CB Systems & Service Guide

141 Chapter 12 Techical Support How To Reach Us I order to provide you with the most comprehesive techical support, (hardware or software), please complete the followig problem report before cotactig PaxSca techical support persoel. If you prefer ig the iformatio to us, a.pdf versio of this form is icluded o the CD ROM you received with your system. You may also fax a completed copy of the problem report prited o the followig page. To speak with our techical support persoel, call (800) or (801) the report to paxsca.service@varia.com, the call the above umber. Fax a copy of the Problem Report to (801)

142 PaxSca 3030CB / 4030CB Problem Report Customer Iformatio Date: Compay Name: Your Name: Phoe: Fax: Product Iformatio PaxSca Part Number: Software Revisio #: Receptor Serial Number: Operatio I was tryig to perform (be as specific as possible): What happeed (use additioal sheets as ecessary): Fax this report to: (801) or paxsca.service@varia.com PaxSca 3030CB / 4030CB Systems & Service Guide

143 Appedix A Glossary Aliasig Amorphous Silico a-si Cesium Iodide Cliet or Cliet Computer Cotrast Trasfer Fuctio (CTF) Correctio Iterferece patters produced by the iteractio of high spatial requecy iformatio i the image with the pixel matrix. Silico that is deposited from vapor to form a thi, o-crystallie film. Commo itegrated circuits are made from crystallie silico wafers sliced from grow crystals. Amorphous silico devices ca be much larger i area tha the crystallie variety because o sigle crystal is eeded. Amorphous silico is ideal for X-ray detectors because it is early immue to radiatio damage. For use i imagig devices, amorphous silico is permeated with hydroge (a-si:h) ad diffused with P ad N dopats to provide device juctios. The most efficiet scitillator i the diagostic X-ray eergy bad. Cesium iodide has both high X-ray absorptio ad high visible photo yield. The sodium-doped versio (CsI:Na) produces blue light ad is used with photocathodes i uclear particle detectors ad X-ray image itesifier tubes while the thallium-doped type (CsI:Tl) is used with silico detectors because it produces gree light. CsI:Na is strogly hygroscopic ad deliquescet ad geerally uusable outside cotrolled eviromets. CsI:Tl is moderately hygroscopic but easily protected makig it suitable for use i air. For imagig, both types are grow i the form of desely packed thi colums to provide a fiber-optic, light-guidig effect for improved resolutio. Refers to the OEM computer. A measure of the ability of a imagig device to accurately reproduce patters cosistig of alteratig dark ad light bars of various widths. These bar patters are calibrated i lie pairs (oe black ad oe white bar of equal width together) per millimeter (lp/mm), called spatial frequecy. The differece betwee the maximum sigal i the white bar ad the miimum sigal i the black at several spatial frequecies divided by the differece whe very wide bars are used is plotted agaist the spatial frequecy. The curve is the cotrast trasfer fuctio. May refer to offset, gai, defective pixel or digital lie oise reductio. All are selectable from the ViVA pulldow meu uder Acquisitio->Mode Settigs. Dark Curret Dark Field Detective Quatum Efficiecy Sigal resultig from leakage i the devices makig up the sesor pixels. A image take "i the dark;" o X-rays. A measure of the ability of a imagig device to covert a icomig image to a electrical sigal without addig oise. Precisely, it is the square of the ratio of the outgoig sigalto-oise (SNR) i the electrical sigal divided by the icomig SNR i the X-ray sigal. DQE usually varies with spatial frequecy because the shape of the oise spectrum almost always differs from the shape of the modulatio trasfer fuctio. A A 143

144 Direct X-ray Detectio Fill Factor Flat Field or Flood Fluoroscopy FPGA Idirect X-ray Detectio Lag Limitig Resolutio LVDS MIPS Detectig X-ray eergy by measurig charge geerated directly by absorptio by absorptio of X-rays. Gases (xeo), liquids (iso-octae) or solids (seleium) ca serve as the coversio materials. The charge may be measured by sesig electrostatically-iduced chages i surfacevoltage or by collectig the charge itself. The fractio of the total area of a sesor that ca covert icomig light ito stored charge for readout. A image take with X-rays ad o object i the path of the Field beam. Real-time X-ray imagig, usually performed at low dose rates. Field Programmable Gate Array. Detectig X-ray eergy by first covertig it to visible light with a scitillator. The light is detected by a photodiode or similar opto electroic device. The scitillator may be i direct cotact with the photodiode detectors or coupled via fiber optics or leses. The percetage of the sigal produced by a sesor some specified umbers of scas after illumiatio is termiated to the sigal produced uder steady-state illumiatio. The smallest set of bars visible i a image produced by a sesor. I usampled systems, this is ofte specified at the 3% modulatio poit. I sampled systems that are limited by the first samplig mechaism, it is exactly the spatial frequecy at which oe lie pair covers two pixels. Low Voltage Differetial Sigalig. Millio Istructio Per Secod. Modulatio Trasfer Similar to Cotrast Trasfer Fuctio but with a patter cosistig of sie waves rather Fuctio (MTF) tha bars. The amplitude of the sigal at ay selected spatial frequecy is called the modulatio depth for that frequecy. It is possible to determie the MTF of a overall system by multiplyig the MTF data from the idividual compoets together. MOPS NDE NDT Multi Output Power Supply. No-destructive evaluatio, a idustrial applicatio. No-destructive testig, a idustrial applicatio. Pixel Pitch Pseudo Emitter Coupled Logic. The limitig resolutio of a specific pixel matrix is give by the formula: R = 1/2d where d is the pixel pitch i millimeters ad R is the limitigresolutio i lie pairs per millimeter. A 144 PaxSca 3030CB / 4030CB Systems & Service Guide

145 Quatum Efficiecy Radiography Radioscopy Raw Image Recursive Filter Scitillator Server SNR Tape Automated Bodig (TAB) The ratio of the umber of charge carriers produced to the umber of icomig visible photos. Oly the photos actually received o a photosesitive area are couted. The average quatum efficiecy of the sesor pael is the photodiode quatum efficiecy times the fill factor. A image produced o a radiosesitive surface by radiatio other tha visible light, especially by X-rays passed through a object. Examiatio of the iteral structure of optically opaque objects by use of peetratig radiatio, especially by X-rays. A ucorrected image. A temporal filter used to reduce oise i low dose fluoroscopic applicatios, at the expese of icreased image lag. The itrisic lag of the a-si pael is somewhat less tha that foud i a plumbico. The recursive filter combies a weighted average of the prior image frames with the curret iput frame. The recursive filter algorithm is: output frame = (1 α) x (ew frame) + α (old frame) where α ca take o values betwee 0 ad Recursive filterig itroduces a cotrolled amout of lag ito the video output for the purpose of oise reductio. This is a commo techique i fluoroscopy, where the sigal levels are very low ad there is sigificat oise itroduced by the statistics of the X-ray beam itself. A compoud that absorbs X-rays ad coverts the eergy to visible light. A good scitillator yields may light photos for each icomig X-ray photo; 20 to 50 visible photos out per 1kV of icomig X-ray eergy is typical. Scitillators typically cosist of a high-atomic umber material, which has high X-ray absorptio, ad a low-cocetratio dopat which provides direct bad trasitios to facilitate visible photo emissio. Scitillators may be graular like gadoliium oxysulfide or crystallie like cesium iodide. I the Server/Cliet relatioship, the Server refers to the PaxSca 3030CB / 4030CB Commad Processor, ad the Cliet to the OEM Computer. Sigal-to-oise ratio. Each row ad colum o a sesor pael must be idividually coected to exteral electroics. The spacig of these coectios is usually less tha the pixel pitch. To coect to the thousads of cotacts, small, flexible prited circuits are used which each cotai a itegrated circuit to cocetrate the may sigals o the glass (typically 128 or more) ito fewer cotacts (perhaps 20 to 30). The lower desity ed is coected to the glass usig a aisotropic coductive film (ACF) uder cotrolled temperature ad pressure. Sice the flexible circuits typically come o a reel-like film ad, at least i high volume, the attachmet process is doe by machie, the techique is called tape automated bodig ad the process is called TAB attachmet. For coveiece, the small flexible circuits are ow called TABs, which they coveietly resemble. A TFTs Thi Film Trasistors. A 145

146 ViVA Workstatio Varia Image Viewig ad Applicatio software. Workstatio computer, also referred to as cliet. A 146 PaxSca 3030CB / 4030CB Systems & Service Guide

147 Appedix B Commad Processor ad Computer Iterface Determiig IP Addresses I order for the Commad Processor ad the PC Workstatio to commuicate over the Etheret port, each address must be recogized. There are two possible eviromets. The first is simply a poit-to-poit coectio betwee the Commad Processor ad Workstatio. The secod possibility is that both the Workstatio ad Commad Processor are coected to a local etwork. This sectio addresses the cofiguratio ad operatio for the PaxSca 3030CB / 4030CB with a Basic Workstatio. I this cotext, the Commad Processor is also referred to as the Server. The OEM Workstatio is the Cliet, sice it uses the services provided by the Commad Processor. If the Commad Processor ad the workstatio are coected to a local etwork, cotact the etwork admiistrator to obtai the IP address for both the workstatio ad the Commad Processor. These addresses ca the be set as described below. If the imagig system is coected i a poit-to-poit cofiguratio, a special RJ45 to RJ45 crossover cable is required. I the poit-to-poit cofiguratio, we recommed the use of the followig addresses: Commad Processor 172:20:20:20 Workstatio 172:20:20:21 Importat: Usig these addresses will protect the local etwork i case of accidetally coectig the Commad Processor or Workstatio to the Network. Settig the IP Address of the Commad Processor 1. The Commad Processor should be tured OFF. 2. Click the Hostdow ico. The followig scree appears: B B 147

148 3. From the meu bar select Cofigure->Commuicatios Port->COM 2; click Coect. The followig widow opes: 4. Whe this widow opes, power ON the Commad Processor. The followig widow will ope whe a coectio is established: 5. Click OK. If the attempt to establish the coectio fails, repeat the procedure usig the COM1 port. 6. After clickig OK, the followig widow opes: 7. From the meu bar select Target Commads->Chage Target s IP Address. The followig widow opes: 8. Eter IP addresses ad click Set IP Now. 9. Cycle power o the Commad Processor. The address chage is complete. B 148 PaxSca 3030CB / 4030CB Systems & Service Guide

149 Settig the IP Address of the Workstatio Assumig the workstatio operatig system is Widows NT, the IP address ca be cofigured as follows: 1. From the Start meu, select Settigs, the Cotrol Pael. 2. Double click the Network ico. 3. Click Protocols tab, as show below: 4. Double click TCP/IP Protocol or select Properties 5. For poit-to-poit Etheret coectios, eter each address as show below. For coectio to a local etwork, cotact the etwork admiistrator for IP, Subet Mask ad Gateway Default addresses. B B 149

150 B 150 PaxSca 3030CB / 4030CB Systems & Service Guide

151 Appedix C Calibratio Procedure 3030CB / 4030CB - High Dyamic Rage modes 1.0 Itroductio This documet describes the calibratio ad image ormalizatio of the high dyamic rage modes available from Paxsca 3030CB / 4030CB imagers. Calibratio ad ormalizatio of 3030CB / 4030CB "ormal" 14 bit modes (or "static gai" modes) ca be hadled by the commad processor i the same way as ay Paxsca 4030A mode. 1.1 High dyamic rage operatio The high dyamic rage modes i the 3030CB / 4030CB are achieved by dyamically makig multiple gai selectio for each image pixel. Normalizatio of images acquired i the Paxsca 3030CB / 4030CB high dyamic rage modes, is ot possible usig the ormalizatio capabilities of the Paxsca commad processor. These images have to be ormalized o the host system computer. To facilitate this ormalizatio, a dyamically liked library file that cotais the ecessary fuctios to calibrate ad ormalize these high dyamic rage modes, is available Dual gai readout image format Sigal from each pixel is "read" twice for each image frame, first at high gai ad agai at low gai. Oly available as 2x2 biig optio. Output images have 1024 x 1536 pixels (i.e. double height). The first lie of each output image cotais data for the first bied lie of the imager, acquired i high gai selectio. The secod lie cotais data for the same imager lies, but acquired i low gai selectio. This sequece is maitaied up to the middle of the image, where two low gai lies are foud, after which the low gai / high gai lie sequece is reversed Dyamic gai switchig image format Pixel sigals are read out oce, at either high or low gai. The selectio is made automatically by a level sesig circuit, pixel-by-pixel, based o its exposure level. The gai is reduced automatically for pixels with high exposure ad their pixel data are flagged with a gai bit for later ormalizatio. Images will be stadard size, but will appear wrog, due to image regios that were acquired at substatially lower gai. Images are stadard size images cotaiig 2048 x 1536, 1024 x 768 or 512 x 384 pixels (depedig o biig). Each pixel cotais 14 bits of pixel data (bits 0 though 13) ad a gai bit (bit 14), which is set high if the pixel data was acquired at low gai. Images will have pixel values ragig from 0 to for high gai pixels ad from to for low gai pixels. C C 151

152 1.2 Fuctio of the DLL The VIP_4030CB.DLL library helps the user's software applicatio to ormalize 3030CB / 4030CB high dyamic rage images (establish a "software commad processor" o the host PC). Normalizatio ivolves: Compesatio of the imager gai ad offset o-uiformities. Iterpolatio of defective pixels. Re-iterpretatio of the multi-gai data from each pixel ito sigle, liear data words. This reduces the double size images from dual gai readout, to stadard size. I order to achieve optimum speed of operatio ad miimal use of PC resources, the DLL uses iteger mathematics for almost all ormalizatio ad restoratio calculatios. Use of the DLL also requires access to its associated header (VIP_4030CB.h) ad library (VIP_4030CB.lib) file durig compilatio of the user applicatio ad to the.ii file durig rutime. The VIP_4030CB.h file defies the class which provides the software support for the 3030CB / 4030CB. After creatig the class, the user must call iitialize() passig the path to the directory cotaiig the INI file ad the calibratio files, if they exist. 1.3 The.ii file Cofiguratio ad setup data relevat to the particular high dyamic rage mode i use, is commuicated to the DLL via VIP_4030CB.ii. The.ii file is supplied/edited by the user. Most of the parameters i the INI file are self explaatory. The iitializatio call to the DLL (iitialize( cost char base_dir[] )), supplies the directory where the.ii file is located. This directory will/must also be used to store calibratio data, such gai ad offset data ad defect maps. The Data_type parameter idicates whether the pael is operatig i dual readout mode or dyamic switchig mode (see VIP_4030CB.h file for defied values). The ROI parameters defie the regio which is used whe determiig the media value of a image (the ROI should at least exclude the 3 mm scitillator "shoulder" regio of the imager, as well as ay regios that are ot exposed to X-ray durig gai calibratio). The various limit parameters set the percetage of media that a pixel eeds to exceed, to be cosidered a defect. 1.4 Defect map Locatios of defective pixels are stored i defect map image files. A distictio is made betwee "auxiliary" defects ad "base" defects. The base defect map is compiled at imager productio ad ca oly be chaged by user editig, usig the ViVA defect editor. Auxiliary defects are detected durig gai calibratio. The auxiliary defect map is calculated from scratch at every calculatio ad cotais o history. For stadard sigle gai modes (i.e. where the commad processor is used for ormalizatio), these defect maps are 16 bit image files that are stored o the commad processor (exactly the same as the Paxsca 4030A). C 152 PaxSca 3030CB / 4030CB Systems & Service Guide

153 For high dyamic rage modes (i.e. where the DLL is used for ormalizatio), defect maps are stored as more efficiet biary image files, i a format that combies both base ad auxiliary defect iformatio. Oe defect map is stored for each gai selectio, o the host PC, i the same directory as the.ii file (fileames Hi_G_defect_map.bi ad Lo_G_defect_map.bi). Each pixel o the imager is represeted by 2 cosecutive bits: oe auxiliary defect bit, which is recalculated by the DLL at every gai calibratio ad oe base defect bit, which ca oly be modified by the ViVA defect editor. Comprehesive defect detectio is a complex process, requirig a rage of computatioally itesive search algorithms to be performed o a set of images ad image sequeces that are acquired over a rage of coditios. Some of these algorithms require extesive operator iteractio. Comprehesive defect detectio is thus ot a process that should form part of a user level calibratio - it is best left to skilled flat pael productio persoel. The purpose of the base defect bit for each pixel is thus to store the comprehesive, productio level defect iformatio, i a maer that will prevet modificatio durig ormal calibratio. The auxiliary defect bit for each pixel is re-calculated, at each gai calibratio, by a rudimetary algorithm that simply marks all pixels that fall outside a preset fractioal rage of the gai ad offset image medias. These defect thresholds are programmable through the.ii file, by adjustig the XXX_offset_limit_XXX ad XXX_gai_cal_limit_XXX parameters (these parameters idicate defect thresholds, as a percetage of the image media). Should a defect appear durig the life of the imager, but it is ot reliably detected by the auxiliary defect detector, it ca be added to the base map, usig the ViVA defect editor. 2.0 Performig Calibratio 2.1 Backgroud ifo The user software applicatio must iitiate imager calibratios: Offset calibratios as frequetly ad as close to image acquisitio time as possible. As a rule offset calibratios should be performed at least every 30 miutes, or prior to each CBCT sca. More frequet offset calibratios are importat while the imager temperature is ot stable (e.g. after power-up). Gai calibratios periodically - experiece has show oce a moth to be a good rule of thumb. More exact applicatios, such as CBCT, may require more frequet calibratios, as determied through experiece. "Calibratio" requires the user software to accumulate 32 bit "sum" images from the receptor (the total of a sequece of frames) ad passig them to either the gai or offset calibratio fuctio i the DLL. All commad processor ormalizatio fuctios have to be tured off durig acquisitio of calibratio images. Gai calibratio requires the acquisitio of a dark field sum image (o X-ray) ad a flat field sum image (exposed to X-ray) for both gai selectios used i the applicable high dyamic rage mode. The gai_calibrate() fuctio i the DLL calculates the 32 bit differece betwee the flat field ad dark field image. This gai image is scaled ad stored as either Hi_G_gai_img.viv or Lo_G_gai_img.viv, i the same directory as the.ii file. C C 153

154 Each file cotais a value for either the relative high gai ( G HG ) or low gai ( G LG ) of each pixel (absolute values are ot relevat). The media values for the high gai image ( G HG ) or low gai image ( G LG ) are also calculated by the gai_calibrate() fuctio ad stored i the header of the applicable gai image file. To allow the use of bow tie filters or o-uiform X-ray fields, the media is oly calculated over the regio defied by the ROI_XXX parameters i the.ii file. If it is deemed ecessary, the user software applicatio ca ow re-calculate the media gai ratio ( R G ) betwee high ad low gai. The media value for both XXX_ gai_img.viv images must be calculated (preferable i the ROI regio oly) ad the ratio of these umbers stored i the.ii file (as the HL_ratio parameter), usig the set_hl_ratio() fuctio. Offset calibratio requires the acquisitio of a dark field sum image (o X-ray) oly. Whe passig this sum image to the offset_calibrate() fuctio i the DLL, the offset image is calculated by appropriate scalig ad stored as either Hi_G_ofst_img.viv or Lo_G_ofst_img.viv, i the same directory as the.ii file. Each file cotais a value for the absolute offset of each pixel, i either high gai ( O HG ) or low gai ( O LG ) selectio. Defective pixels are also detected by the gai_calibrate() fuctio. The oly defects detected, are those pixels fallig outside the boudaries set by the applicable XXX_gai_cal_limit_XXX or XXX_offset_limit_XXX paramters i the.ii file. These defects are stored as auxiliary defects oly (see below). Whe usig dual gai readout modes, the offset calibratio ad ormalizatio capabilities of the commad processor ca be used, istead of the DLL ormalizatio fuctios, as described above. To use this shortcut, the Hi_G_ofst_img.viv ad Lo_G_ofst_img.viv images must be replaced by appropriate ull images, with the same ames, after completio of gai calibratio. Offset calibratio i the commad processor must be tured off prior to gai calibratio ad tured back o after gai calibratio. Offset calibratios the requires the trasmissio of a sigle "offset calibrate" commad to the commad processor. This approach is ot valid whe usig dyamic gai switchig modes. All commad processor correctios must be tured off whe usig these modes. The calibratio process requires a differet sequece of actios, depedig o whether dual gai readout mode or dyamic gai switchig mode is used. 2.2 Calibratio of dual gai readout modes The DLL must be iitialized for dual gai readout mode. This is doe by poitig to a.ii file with the parameter Data_type = 1 durig the call to the iitialize() fuctio i the DLL Gai Calibratio procedure A. If ot already selected, the user software selects the dual gai readout mode to be calibrated. The mode may be described by a strig such as "4030CB bi G1 0p5/4p DGR" (where bi = 2x1 or 2x2). C 154 PaxSca 3030CB / 4030CB Systems & Service Guide

155 B. With o X-ray exposure, the user software accumulates the sum of a sequece of images (128 images will typically suffice) from the frame grabber. C. This sum image is passed to the offset_calibrate() fuctio twice - oce with the gai_mode fuctio variable set to HI_G_MODE, to calculate ad store the offset image for the high gai selectio ad oce with the gai_mode variable set to LO_G_MODE, to calculate ad store the offset image for the low gai selectio. D. Next, the user or user software must set up a X-ray exposure that is high eough for most pixels to be ear the saturatio level i the high gai lies of the ucorrected composite image. The absolute value of the exposure is ot of importace, but a suitable value may require some experimetatio. E. After the X-ray exposure is iitiated, the user software accumulates the sum of a sequece of images (128 images will typically suffice) from the frame grabber. F. This sum image is passed to the gai_calibrate() fuctio, with the gai_mode variable set to HI_G_MODE, which calculates ad stores a gai image for the high gai selectio. G. (OPTIONAL) If the ratio betwee low ad high gais eeds to be determied, the above sum image ca be passed to the gai_calibrate() fuctio agai, with the gai_mode variable set to LO_G_MODE, which will calculate ad store a gai image for the low gai selectio. The user software applicatio ca ow calculate the media gai ratio ( R G ) betwee high ad low gai. The media value for both XXX_ gai_img.viv images must be calculated (preferable i the ROI regio oly, as defied i the.ii file) ad the ratio of these umbers stored i the.ii file (as the HL_ratio parameter), usig the set_hl_ratio() fuctio. I our limited experiece, it is sufficiet to calculate this value oce for each imager, durig system maufacture. H. It is recommeded that a secod gai calibratio be performed at a much higher X-ray exposure, for the low gai selectio oly. I. Set up a exposure that is high eough for most pixels i the low gai lies of the ucorrected image to be ear, but below the saturatio level. J. After the X-ray exposure is iitiated, the user software accumulates the sum of a sequece of composite dual gai images (128 images will typically suffice). K. This sum image is passed to the gai_calibrate() fuctio, with the gai_mode variable set to LO_G_MODE, which calculates ad stores a gai image for the low gai selectio Offset calibratio procedure A. If ot already selected, the user software selects the dual gai read-out mode to be calibrated. The mode may be described by a strig such as "4030CB bi G1 0p5/4p DGR" (where bi = 2x1 or 2x2). B. With o X-ray exposure, the user software accumulates the sum of a sequece of composite dual gai images (128 images will typically suffice). C. This sum image is passed to the offset_calibrate() fuctio twice - oce with the gai_mode variable set to HI_G_MODE, to calculate ad store the offset image for the high gai selectio ad oce with the gai_mode variable set to LO_G_MODE, to calculate ad store the offset image for the low gai selectio. C C 155

156 2.3 Calibratio of dyamic gai switchig modes The dyamic gai switchig mode is ot supported at this time. The DLL must be iitialized for dyamic gai switchig mode. This is doe by poitig to a.ii file with the parameter Data_type = 0 durig the call to the iitialize() fuctio i the DLL. 3.0 Performig Image Normalizatio ad Restoratio 3.1 Backgroud The 3030CB / 4030CB dll performs offset ad gai correctio ad defective pixel correctio. Commad processor ormalizatio fuctios are tured off durig acquisitio i high dyamic rage modes (except whe usig the commad processor to perform offset correctio i dual gai readout modes - see above). Ucorrected raw images are passed to the correct_image() fuctio i the DLL. Normalized X-ray itesity values for each pixel are calculated accordig to the formula (see paragraph 2.1 for a descriptio of the symbols):, for high gai pixel data (D pixel, HG ) ad, for low gai pixel data (D pixel, LG ). This calculatio completes the ormalizatio task for images acquired with dyamic gai switchig modes. I this case, the decisio to calculate ad use either I pixel, HG or I pixel, LG is based solely o the value of the gai flag that is preset i each pixel data word received from the imager. For images acquired i dual gai readout modes, the decisio to use either the low gai or high gai pixel data values is made for each pixel, as part of the ormalizatio calculatio. Two software threshold levels, T low ad T high are defied i the.ii file (parameters Threshold_A ad Threshold_B). For all pixels with D pixel, HG below T low, the I pixel, HG value is used as the represetative equivalet itesity. For all pixels with D pixel, HG above T high, the I pixel,lg, value is used as the represetative equivalet itesity. For pixels with D pixel, HG betwee T low ad T high, a liear iterpolatio of ad I pixel, HG ad I pixel, LG value is used, thus guarateeig a smooth trasitio i image regios with itesity ear the trasitio threshold. The effective image bit depth is ow larger tha 16 bits. To reduce data back to 16 bits per pixel, the correct_image() fuctio will compress output images ito a pseudo floatig poit format. The corrected image will agai cotai 14 bits of pixel data ad 2 bits idicatig the amout to shift the 14 data bits. To restore compressed images, the gai bit ca be used as a look-up table address bit or it is aticipated that sufficiet liearity may be achieved by multiplyig pixels flagged by the gai bit, by the gai ratio value (see "calibratio" above). The result of this de-compressio operatio will be more tha 16 bits per pixel. C 156 PaxSca 3030CB / 4030CB Systems & Service Guide

157 Alteratively, the DLL also cotais a fuctio that ca be used to provide a corrected, scaled, liear, 16 bit versio of the raw image. This is achieved by scalig the data by a factor supplied by the user. Ay resultig values greater that will be set to The dll requires a directory i which the followig files are stored (A sample.ii file is provided, the other files required i the directory will be geerated by the dll whe calibratio is performed.): 1. INI parameter file - This file commuicates imager setup ad user preferece ifo to the DLL. It has to be edited by the user 2. High gai offset file - this file is calculated by the offset_calibrate() fuctio, from a sum image accumulated by the user software as described below. 3. Low gai offset file -similar to High gai offset file. 4. High gai gai image file - this file is calculated by the gai_calibrate() fuctio, from a sum image accumulated by the user software as described below. 5. Low gai gai image file - similar to High gai gai file. 6. High gai defective pixel map - this file cotais a auxiliary defect map, as calculated by the gai_calibrate() fuctio ad a base defect map that is calculated at imager productio ad editable by the ViVA defect editor. 7. Low gai defective pixel map - similar to High gai defective pixel map file. 3.2 Performig ormalizatio The correct_image() routie performs the offset ad gai correctio ad defective pixel correctio. The supplied 16 bit image is replaced by the corrected 16 bit image. Each pixel value cotais the corrected pixel value i the low order 14 bits ad a shift value i the high 2 bits. Wheever the true pixel value must be used i a applicatio of for display, a table lookup must be performed to obtai the desired pixel value. For images acquired i dual gai readout modes, the corrected image is oly half the size as the supplied image. The.ii parameters Threshold_A ad Threshold_B are oly used for dual readout images. The offset ad gai corrected value for the high gai readig is first determied. If the high gai value of a pixel is below Threshold_A, this is the corrected pixel value. If the high gai value is above Threshold_B, the corrected pixel value is determied from the corrected low gai readig. If the value is betwee Threshold_A ad Threshold_B, iterpolatio is performed betwee the high gai ad low gai corrected readigs to isure a smooth trasitio. The geerate_scaled_image() fuctio ca be used to produce a liearized versio of the compressed data format images produced by correct_image(). C C 157

158 C 158 PaxSca 3030CB / 4030CB Systems & Service Guide

159 Appedix D Multiple gai ragig readout method to exted the dyamic rage of amorphous silico flat pael imagers. Pieter G. Roos* a, Richard E Colbeth a, Iva Mollov a, Peter Muro b, Joh Pavkovich a, Edward J. Seppi a, Edward G. Shapiro b, Carlo A. Togia a, Gary F. Virshup a, J. Michael Yu a, George Zetai a, Wolfgag Kaissl c, Evagelos Matsios c, Jeroe Richters c, Heirich Riem c, a Varia Medical Systems, Gizto Techology Ceter, 2599 Garcia Ave, Moutai View, CA b Varia Medical Systems, Ocology Systems Divisio, 3100 Hase Way, Palo Alto, CA c Varia Medical Systems, Imagig Laboratory, Neuehoferstrasse 107,5400 Bade, Switzerlad ABSTRACT The dyamic rage of may flat pael imagig systems are fudametally limited by the dyamic rage of the charge amplifier ad readout sigal processig. We developed two ew flat pael readout methods that achieve exteded dyamic rage by chagig the readout charge amplifier feedback capacitace dyamically ad o a real-time basis. I oe method, the feedback capacitor is selected automatically by a level sesig circuit, pixel-by-pixel, based o its exposure level. Alteratively, capacitor selectio is drive exterally, such that each pixel is read out two (or more) times, each time with icreased feedback capacitace. Both methods allow the acquisitio of X-ray image data with a dyamic rage approachig the fudametal limits of flat pael pixels. Data with a equivalet bit depth of better tha 16 bits are made available for further image processig. Successful implemetatio of these methods requires careful matchig of selectable capacitor values ad switchig thresholds, with the imager oise ad sesitivity characteristics, to isure X-ray quatum limited operatio over the whole exteded dyamic rage. Successful implemetatio also depeds o the use of ew calibratio methods ad image recostructio algorithms, to isure artifact free rebuildig of liear image data by the dowstream image processig systems. The multiple gai ragig flat pael readout method exteds the utility of flat pael imagers ad paves the way to ew flat pael applicatios, such as coe beam CT. We believe that this method will provide a valuable extesio to the cliical applicatio of flat pael imagers. Keywords: Flat pael, coe beam CT, charge amplifier, gai switchig, dyamic rage, radiography, dual gai, multiple gai Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D D 159

160 1.0 INTRODUCTION 1.1. The eed for exteded dyamic rage Most commoly available amorphous silico flat pael X-ray imagig systems deliver digital image data with a digital depth of 12 bit or 14 bit. While extesive experiece has show that these systems achieve sufficiet quatizatio resolutio to perform excellet radiographic imagig, certai demadig applicatios, such as subtractio agiography ad coe beam computer tomography (CBCT), will beefit from the higher dyamic rage ad better quatizatio resolutio afforded by 16 bit, or higher, quatizatio. This is especially true i the case of flat pael based CBCT, where 14 bit liear projectio data ca be used to recostruct oly adequate volumetric images, while 16 bit data acquisitio facilitates the recostructio of good quality volumetric images. The quality of flat pael based CBCT imagig is deteriorated by 14 bit projectio data acquisitio, maily through three mechaisms: 1) large relative errors i beam itesity values measured through dese aatomy, resultig from too large quatizatio steps, cause streak artifacts off dese objects, 2) isufficiet resolutio of pixel gai ad offset ormalizatio causes rig artifacts i third geeratio CBCT systems ad 3) trucatio of low desity aatomical detail at patiet extremities, due to isufficiet dyamic rage, results i shadow artifacts ad icorrect Houdsfield umbers. The effects of the first two degradatio mechaisms are clearly visible i Figure 1, while the third degradatio mechaism is discussed by a umber of authors, such as Seeram [4]. Figure 1 Flat pael CBCT images of a head phatom: 16 bit system (left) ad 14 bit system (right) 1.2. Limitatios of flat pael imagers Oe commoly used idicator of the dyamic rage capability of a flat pael based imagig system is the ratio of the system's RMS electroic oise, expressed as a equivalet sigal value, to the sigal level where sufficiet o-liearity occurs for the pixel ormalizatio process to fail. The available oise-to-saturatio dyamic rage of commercial flat pael based imagig systems is typically less tha the 16k:1 quatizatio rage afforded by its 14 bit A/D coversio. O the other had, the fudametal limit to the dyamic rage of amorphous silico flat paels, as imposed by amorphous Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D 160 PaxSca 3030CB / 4030CB Systems & Service Guide

161 silico pixels, may be well i excess of 50,000:1. The opportuity for icreased dyamic rage ca be described by the followig qualitative argumet: a easy measuremet of a commercially available flat pael based imagig system, with 194 µm TFT/photodiode pixels [1], shows such a system to achieve a electroic oise level of better tha 1700 equivalet electros RMS pixel oise, whe used without ay pixel biig. Based o the pixel capacitace ad bias voltage, the pixels of this flat pael will oly saturate at a accumulated sigal charge of approximately 50 millio electros. Thus, the potetial oise-to-saturatio dyamic rage for this imager is 30,000:1, whe read out without ay pixel biig. A similar argumet cocludes that this same imager could achieve a oise-to-saturatio rage of 60,000:1 whe 2x2 pixel biig is used ad 240,000:1 whe 4x4 biig is used. Applyig such argumets to differet flat pael detector types will reveal similar urealized dyamic rage capabilities for most imagig systems. I the majority of imager applicatios, the accumulated charge sigals i the flat pael pixels are detected ad coverted to voltage sigals by meas of multiple, parallel charge itegratio amplifiers, as depicted i Figure 2. The characteristics of these charge itegratio amplifiers ad the subsequet sigal processig electroics impose the actual limits o the dyamic rage available from practical flat pael based imagig systems. I TFT/photodiode type imagers, the icomig X-ray projectio image is coverted to a light image by a scitillator layer. This light image is detected by the matrix of amorphous silico photodiodes of the flat pael detector ad the accumulated sigal charge is stored o the photodiode capacitace util readout occurs. Durig the readout phase, the accumulated sigal charge of each pixel is trasferred sequetially to the itegratio capacitor (C1 i Figure 2) of a readout amplifier chael, thus covertig the charge sigal to a voltage sigal. The voltage sigal is processed through a sample-ad-hold circuit ad correlated double samplig (CDS) corrected, multiplexed ad the coverted to a digital word stream. I most systems, the charge amplifier, sample-ad-hold, CDS ad multiplexig fuctios are implemeted i multi-chael custom ICs, while the aalog-to-digital coversio fuctio is performed by commercial, off-the-shelve A/D coverters. Figure 2 A symbolic represetatio of a typical a:si flat pael detector readout method Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D D 161

162 The low ed of a flat pael imager's dyamic rage is limited by oise geerated i the pixels ad sigal processig chai. Noise sources iclude pixel ktc oise, thermal oise geerated by imager data lies, charge amplifier voltage oise ad oise geerated i the sigal processig chai [2, 3]. I Varia's Paxsca 3030CB / 4030CB imager, that was developed to take advatage of the read out methods that are described here, these sources add up to approximately 1700 electros RMS equivalet itegrator charge, as metioed above. O the other had, the high ed of this dyamic rage is usually determied by the voltage swig that ca be achieved by the charge amplifier ad sigal processig chai, while maitaiig sufficiet liearity to facilitate subsequet pixel gai ad offset ormalizatio. For the above system, this poit is reached at about 2 volt swig, or 6 millio electros stored o the 0.5 pf itegratio capacitor. This yields a 3,500:1 oise-to-saturatio dyamic rage, which matches very well with the 16k quatizatio steps available from a 14 bit A/D coverter. Usig a 1 pf itegratio capacitor, as i Varia's Paxsca 4030A imagig system, will achieve a dyamic rage i the order of 6,000:1. These rages are however very substatially less tha the actual dyamic rage available from the amorphous silico flat pael detector. Chagig the capacitor will typically ot result i a icrease i dyamic rage - decreasig the capacitor may decrease equivalet electroic oise, but will cause saturatio at lower exposure; icreasig the capacitor will icrease the saturatio exposure, but may cause alterate oise sources to become domiat at low exposure levels. A alterative readout architecture is required i order to realize the dyamic rage capabilities of flat pael detectors i practical imagig systems. 2.0 MULTIPLE GAIN RANGING READOUT METHOD I order to achieve a flat pael based imagig system with dyamic rage approachig the capability of the amorphous silico flat pael, we developed a ew charge readout amplifier IC that is capable of chagig the charge amplifier feedback capacitace of each chael dyamically ad o a real-time, pixel-by-pixel basis. Each amplifier chael also icludes a latched comparator that ca be eabled to chage the feedback capacitace automatically, based o the amout of charge preseted to the amplifier, by each idividual pixel. The architecture for this readout method, as implemeted i Varia's Paxsca 3030CB / 4030CB flat pael imagig system, is depicted i Figure 3. Use of this readout architecture eables the implemetatio of two alterative high dyamic rage readout methods Dyamic Gai Switchig I the so-called Dyamic Gai Switchig mode, a comparator is used to icrease the feedback capacitace automatically whe pixels with large accumulated charge are selected for readout. Whe the voltage accumulated i the charge itegrator exceeds the dyamic threshold, which is a global voltage set exterally for all chaels, the comparator switches a additioal, much larger feedback capacitor (C4 i Figure 3), i parallel with the fixed feedback capacitor (C1 i Figure 3). I the 3030CB / 4030CB imager, capacitor values are selected to cause a 8x reductio i gai for pixels that exceed the programmable sigal level. Regardless of whether a pixel was acquired with reduced gai, the sigal from the charge amplifier is the processed through the stadard correlated double samplig circuit ad coverted to a digital word by the 14 bit A/D coverter. To eable recovery of liear pixel data by the dowstream image processor, the output of the latched comparator is sampled by a separate multiplexer ad iserted as a additioal "gai bit" (bit 15 of 16 bits) ito the digital video data word at the output of the A/D coverter. Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D 162 PaxSca 3030CB / 4030CB Systems & Service Guide

163 This provides a marker flag for pixel data that were acquired with reduced gai. Figure 3 Symbolic represetatio of a readout method to ehace flat pael dyamic rage 2.2. Dual Gai Readout The comparator circuit ca also be disabled ad the low gai mode ca the be activated globally, o a pixel-by-pixel basis through the commo "forced low gai" cotrol sigal. This capability is used to implemet the alterative Dual Gai Readout mode, i which the sigal accumulated by each pixel is read twice, first at high gai ad the agai at low gai (i.e. for the same X-ray exposure frame). This is doe without activatig the reset switch i betwee the two readigs. This sequece allows the o-destructive double readig of each pixel sigal packet. Both samples are processed i sequece by the correlated double samplig circuit ad coverted to a digital word each by the 14 bit A/D coverter. Both a high gai ad a low gai value are provided for each pixel, thus resultig i digital image frames with twice the byte size of covetioal images. The Dual Gai Readout mode has the advatage that the gai decisio ca be made i a itelliget maer by the dowstream image processor, but due to the double frame size, the imager ca oly operate at half the frame rate that the imagig system would otherwise be capable of Correlated double samplig Correlated double samplig (CDS) is a importat sigal processig step i the data acquisitio sequece of most flat pael imagers. With referece to Figure 2, this sequece ormally cosists of: 1) activate the RESET switch, 2) activate the S/H2 switch to acquire a ZERO sample of the charge amplifier output, 3) activate the pixel TFT, 4) activate the S/H1 switch to acquire a SIGNAL sample of the charge amplifier output ad 5) subtract the ZERO sample from the sigal sample. CDS has the threefold beefits of 1) cacellatio of the reset KTC oise of the charge amplifier, 2) sigificat reductio of 1/f oise geerated i the charge amplifier ad subsequet circuits ad 3) cacellatio of offset voltage ad the drift i offset voltage of sigal processig circuits, with the exceptio of offset effects geerated i the pixel itself. Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D D 163

164 Sice both high dyamic rage modes described above ivolve chagig the charge amplifier gai after the TFT was activated, this may compromise the validity of the CDS subtractio for low gai data, as the ZERO sample would always be acquired at high gai. Cacellatio of udesirable effects caused i subsequet circuits will obviously be left itact, but the desig of the charge amplifier circuit required special attetio, to isure that its offset ad 1/f oise characteristics do't chage with reductio i gai. Cacellatio of the reset KTC oise will however be ivalid for low gai data ad a icrease i electroic oise will thus be ievitable for low gai data. As will be show i sectio 3, low gai data are oly used where high levels of exposure are ecoutered ad photo oise is sufficietly high to isure quatum limited operatio ad the impact of this additioal low gai oise is thus egligible. This is oly true however whe the jump from high to low gai is ot too large. Low gai oise thus places the limit o the size of gai step ad therefore o the amout of dyamic rage extesio that ca be achieved by ay multiple gai ragig read out method Normalizatio Imager calibratio Whe usig these high dyamic rage readout methods, each pixel is characterized by a uique offset ad gai calibratio value for both low ad high gai selectios. We developed a method of calibratig ad correctig for these o-uiformities, without requirig a accurate kowledge of the x-beam itesity durig calibratio exposures. This results i a easy to perform o-site calibratio that does ot eed ay special equipmet or advaced level of traiig. Dark field ad flat field images are acquired, as durig ay flat pael calibratio procedure [5, 6], but this is doe for both low ad high gai settigs of a high dyamic rage mode. As for a covetioal flat pael, flat field ad dark field images are the average of a sufficiet umber of frames to reduce the image oise to a acceptable level [6]. A method exists whereby the imager ca be forced ito simulated dyamic gai switchig, eve whe o X-ray exposure is preset. For good calibratio quality, two flat field exposures are acquired for the low gai settig: oe flat field image is acquired at the same exposure level as the high gai flat field ad a secod flat field image is acquired at a sigificatly higher exposure. I our method, "gai images" (a 2 dimesioal map of relative pixel sesitivities) are calculated from each of the three flat field images, by subtractig the applicable dark field image. The high gai image ad the high exposure, low gai image are stored for use durig image acquisitio. The low exposure, low gai image is used to calculate the ratio of high-to-low gai ("gai ratio") for each pixel, by dividig it ito the high gai image. This gai ratio image is also stored for use durig image acquisitio. The dark field exposures acquired durig calibratio are discarded. Dark field images, that are used for image offset calculatio, are the acquired for each gai settig, as close as possible to the time of the actual image acquisitio [5]. Five calibratio parameters are thus stored for each pixel (i the form of five calibratio images): the relative high gai (G HG ) ad low gai (G LG ) of each pixel (absolute values are ot importat), the absolute offset of the high gai (O HG ) ad low gai (O LG ) settigs ad the gai ratio (R G ). The media values for the high gai image (G HG ) ad low gai image (G LG ) are also calculated ad stored. Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D 164 PaxSca 3030CB / 4030CB Systems & Service Guide

165 I a simplified versio of the calibratio procedure, oly the media gai ratio for the whole imager is calculated ad applied to all pixels durig image ormalizatio. This obviates the eed to store ad load the additioal gai ratio calibratio image, thus potetially reducig demads placed o the system processor ad memory. As ca be see i Figure 4, the gai ratios of 98% of the pixels of the 4030CB imager fall with 2% of the media gai ratio. However, most of this deviatio from the omial gai ratio is removed by the gai ormalizatio process. It is our experiece that sufficiet accuracy of liearizatio is achieved by usig just the media gai ratio. For demadig applicatios such as high quality coe beam CT, more accurate ormalizatio may be required ad the choice of calibratio methods is thus left to the system desiger. Figure 4 Distributio of pixel gai ratios, as measured for the 4030CB imager Image correctio For each image frame acquisitio, the equivalet itesity value for each pixel is calculated as:, for high gai pixel data (D pixel, HG ) ad, for low gai pixel data (D pixel, LG ). This completes the ormalizatio task for images acquired with the dyamic gai switchig method. For the dual gai readout method, the decisio to use either the low gai or high gai pixel data values is made as part of the ormalizatio calculatio. Two software threshold levels, T low ad T high are defied i software cofiguratio. For all pixels with D pixel, HG below T low the I pixel, HG value is used as the represetative equivalet itesity. For all pixels with D pixel, HG above T high, the I pixel, LG value is used as the represetative of I pixel, HG ad I pixel, LG values is used, thus guarateeig a smooth trasitio i image regios with itesity ear the trasitio threshold. Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D D 165

166 I the case of the dyamic gai switchig method, the decisio to calculate ad use either I pixel, HG or I pixel, LG is based solely o the value of the gai flag that is preset i each pixel data word The Paxsca 4030CB imagig system The Paxsca 4030CB imagig system is a exteded versio of Varia's well kow Paxsca 4030A imager, which is widely used i radiography, fluoroscopy ad agiography applicatios [7]. The 4030CB features the same 2048 x 1536 amorphous silico flat pael matrix, with 194 µm pixels, ad a 39.7 x 29.8 cm active area. The same 600 µm thick Cesium Iodide scitillator is used. The imager is housed i the same housig as the 4030A imager ad is cotrolled by the same commad processor ad power supply. The commad processor is used to cotrol the imager, perform realtime image ormalizatio for the fixed gai modes ad to sed these ormalized images to the eduser's radiography platform, either via a real-time digital video lik or via a stadard Etheret iterface. See referece 1 for a more extesive descriptio of the Paxsca 4030A system. The 4030CB has three selectable itegratio capacitors (0.5 pf, 4 pf ad 16 pf) available to optimize dyamic rage ad exposure rage for specific applicatios. I fixed gai modes, ay of these three capacitors ca be selected, together with 1x1, 2x2 or 4x4 biig, ad a selectio of 1x, 2x or 4x electroic gai. The biig selectio determies the maximum frame rate capability of the imager, as show i Table 1. Additioally the two high dyamic rage read out methods described herei are available, with selectios betwee some of the above capacitor values. These selectios are made available to the user or radiography system via pre-defied modes that are stored i the commad processor. The commad processor supports up to 7 selectable imagig modes at ay oe time. The iterface to the 4030CB will be familiar to existig users of the 4030A, with the oly major differece beig the availability of ew imagig modes ad the requiremets for more complex calibratio procedures for the high dyamic rage modes. Table 1 Maximum frame rate capability of the Paxsca 4030CB 3.0 RESULTS Results reported below are those results that specifically characterize the operatio of the multiple gai ragig methods. Due to the similarity of the 4030CB system with Varia's 4030A flat pael imagig system, we did ot deem it ecessary to report the more commo measures of image quality, such as MTF ad DQE, as these parameters have bee evaluated ad reported elsewhere for the 4030A system [1] ad are mostly idetical betwee the two systems. The oly exceptio is the low dose DQE of the 4030CB system, which beefits from the higher sesitivity of the high gai mode ad the resultat reductio i quatum limit. A formal measuremet of this DQE compariso is ot available at this time, but will be available upo request from the authors i the ear future. Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D 166 PaxSca 3030CB / 4030CB Systems & Service Guide

167 3.1. Dyamic rage Table CB dyamic rage i available imagig modes Saturatio-to-oise rage X-ray exposure rage Digital rage Quatum Saturatio Electroic Saturatio Dyamic Quatizatio Eff. bit limited exposure oise sigal rage rage depth exposure (µr) (ADU) (ADU) (bits) (µr) No biig, gai 2 Dyamic gai switchig : pf fixed : pf fixed : x2 biig, gai 1 Dual gai readout : Dyamic gai switchig : pf fixed : pf fixed : pf fixed, gai 2 (fluoroscopy mode) : Numerous defiitios of dyamic rage exist. For the purposes of compariso with stadard readout methods, the dyamic rage of the 4030CB imagig system was measured i terms of a few of the more commo defiitios of dyamic rage. These results are show i Table 2. For these data, electroic oise was measured as the pixel stadard deviatio of the subtractio of two ucorrected dark field frames, divided by 2. Quatum limited exposure was defied as that exposure where electroic oise equals quatum oise, i.e. where the total image oise = 2 x electroic oise. The results show that multiple gai readout methods offer a icrease of betwee 4 ad 6 times i both dyamic rage ad usable X-ray exposure rage over that offered by sigle gai modes. The potetial 70,000:1 dyamic rage, iheret to 2x2 bied read out, has ot yet bee achieved. This would require a larger step i gai, which would result i o-quatum limited operatio ear the switchover threshold (see below). Some ogoig work to improve this limitatio is described i sectio Sigal-to-oise performace Durig the developmet of the flat pael read out methods described here, we foud the sigal-tooise ratio versus dose behavior of the imagig system to be a very importat measure of the successful implemetatio of multiple gai ragig readout methods. Whe the step betwee high gai ad low gai is made too large, sigal levels i low gai pixels become too low ad the imager o loger achieves quatum limited operatio for exposure levels ear the switchig threshold. This will show up i a SNR vs. dose plot as a deviatio from the ideal quatum limited behavior. The same applies to most crossover artifacts due to icorrect ormalizatio. The SNR vs. dose results, as measured for the Paxsca 4030CB dyamic rage modes, is show i Figure 5. The thick lie was overlaid to show ideal, quatum limited behavior ad plot deviatios from this lie idicate o-quatum limited behavior. Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D D 167

168 Figure 5 Sigal-to-oise performace over the exteded dyamic rage The sigal-to-oise versus dose results idicate that the choice of gai settigs, as implemeted i the Paxsca 4030CB imager, is optimal, give the costraits of the rest of the system. This ca be cocluded from the small deviatio from ideal, quatum limited performace that is visible at exposure levels of approximately 250 µr. This is the itesity eighborhood where low gai data starts beig used. As the sigal levels are relatively low compared to the electroic oise characteristic of the low gai settig, the imager is o the verge of revertig to o-quatum limited operatio. A larger feedback capacitor would have resulted i a too large gai reductio ad electroic oise would have domiated i the trasitio regio. See paragraph 2.3 for a explaatio of the high level of electroic oise applicable to the low gai settig Image artifacts Due to the risk of producig cotour type artifacts i image regios with itesity levels ear the gai switchover threshold, subjective image quality serves as aother importat check o the applicability of our methods to diagostic imagig. Figure 6 shows a slice recostructed from a CBCT sca of a huma pelvis ad Figure 7 shows oe of the projectio images from this sca. These images were acquired with a Paxsca 4030CB based CBCT system usig the dual gai readout method. The projectio image was processed by a severe usharp maskig algorithm, to ehace ay possible boudary artifacts resultig from gai switchig. No such boudary artifacts are visible i either image. The geeral quality demostrated by the CBCT slices of Figure 1 ad Figure 6 also show i geeral the suitability of the Paxsca 4030CB imagig system for CBCT applicatios. Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D 168 PaxSca 3030CB / 4030CB Systems & Service Guide

169 Figure 6 CBCT image of a huma pelvis, acquired with the Paxsca 4030CB imagig system Figure 7 Projectio image of huma pelvis, with usharp maskig 3.4. Other CBCT related performace parameters The performace measuremets reported below are ot affected by the multiple gai readout methods, but due to the CBCT applicatio focus of the Paxsca 4030CB imager, specific attetio was paid to these parameters Image lag Due to the severe image artifacts that could result from image lag i CBCT applicatios, the desig of the Paxsca 4030CB imager was optimized to reduce image lag. The details of this optimizatio are beyod the scope of this article, but for iformatio, the results of a lag measuremet are show i Figure 8. Copyright 2004 Society of Photo-Optical Istrumetatio Egieers. This paper was published i Proceedigs of SPIE, Vol. 5368, February 2004, Sa Diego CA ad is made available as a electroic reprit with permissio of SPIE. Oe prit or electroic copy may be made for persoal use oly. Systematic or multiple reproductio, distributio to multiple locatios via electroic or other meas, duplicatio of ay material i this paper for a fee or for commercial purposes, or modificatio of the cotet of the paper is prohibited. D D 169