Color Line Scan Camera SK22800GJRC-XC

Transcription

1 Color Line Scan Camera SK800GJRC-XC x 7600 pixels (RGB), 9. µm x 9. µm, 10 MHz pixel frequency FAST+ FLEXIBLE Camera SK800GJRC-XC 1 Sensor Type Triple Line Sensor ILX146K Pixel number x 7600 (R-G-B) Pixel size 9. µm x 9. µm Pixel spacing 9. µm Line spacing (R-G-B) 9. µm 4 5 Active length mm Anti-Blooming Integration Control CDS 1 Pixel frequency Line frequency max Line frequency min no no yes 10 MHz 4.9 khz 0.05 khz Integration time max 0 ms Integration time min Dynamic range Spectral range Video signal 0.16 ms 1:1000 (0 MHz) nm 4-bit ( x 8-bit) Interface Voltage +5 V, +15 V Power consumption 7 W Casing (W x H x D) CG7 (84 x 10 x 46 mm) Objective mount Weight 0.4 kg Working temperature +5 C to +45 C 1) CDS = Correlated Double Sampling. Noise-reduction technology, increase of photosensitivity. ) Longer exposure times are possible in trigger mode "Exposure Active" CCD line scan camera SK800GJRC-XC mounted with Focus adapter FA6XC-S55 Extension ring ZR55-15 Lens adapter AC46-55 Macro lens inspec.x L 5.6/105 ß-0.76 Contents SK800GJRC-XC Section Page Section Page 1. Gigabit Ethernet Interface. Connections and I/O Signals. Software and Hardware Installation 4. Camera Setup and Image Acquisition SkLineScan 4 4. Gain / Offset and Shading Correction 4 4. Synchronization Thresholding Continuous Imaging 6 5. SkGigEconfig and Serial Commands 7 6. RGB Sensors: D Imaging and Pixel Allocation 8 7. Control Signals and Timing Diagram 9 8. Sensor Performance Specifications Dimensions Line Scan Camera Fundamentals Features and Characteristics Alignments and Adjustments Warranty Accessories 16 Line scan cameras from Schäfter+Kirchhoff are supplied factory-preset for the particular application. If you are not familiar with line scan cameras, or their operation using the supplied software, then consult the glossary in Section 10. Line Scan Camera Fundamentals, p 14. Kieler Str. 1, 55 Hamburg, Germany Tel: Fax: info@sukhamburg.de

2 1. Gigabit Ethernet Interface CCD line scan cameras of the GJRC-XC series use the Gigabit Ethernet communication protocol, enabling fast image transfer using low cost standard cables up to distances of 100 m. The Gigabit Ethernet interface makes the line scan cameras highly scalable to faster Ethernet speeds, distinguishing them with high performance and total flexibility. All of the GigE cameras from Schäfter+Kirchhoff are externally synchronizable and no grabber board is needed as signal preprocessing is performed inside the camera and does not impinge on CPU use. Additional features include: customer-specific I/O signals in addition to the video signal special preprocessing algorithms can be implemented in the camera consistent attribution of camera IDs in multi-camera operations SDK from Schäfter+Kirchhoff with the SkLineScan operating program, libraries and examples. The camera can be connected to a computer either via the GigE socket directly or through a Gigabit Ethernet switch. Features Shading correction Thresholding Window function (ROI) External synchronization Extra I/O signals User managed buffer queue Sequence acquisition Large image acquisition Multi-camera operation Data cable length Windows LabVIEW X X X X X X X X X, with fixed camera ID 100 m SK91GigE-WIN SDK SK91GigE-LV VI Library Advanced preprocessing Fixed camera IDs for multicamera systems Application: Parallel acquisition using a GigE switch CCD line scan camera 4 Power supply Illumination 5 GigE inter face for transmission of video and control data over distances up to 100 m PC or Notebook with GigE Software, SDKs and ebus driver GigE switch. Connections and I/O Signals 4 5 Power +5 V, 700 ma +15 V, 50 ma Hirose series 10A, male 6-pin 6 1 Pin Signal Pin Signal V 4 +5 V +15 V 5 GND +5 V 6 GND I/O Connector Hirose series 10A, male 1-pin Camera back view 1 1 Data RJ45 con nector for a Gigabit Ethernet cable Pin Signal 1 GND 8 FrameSync 10 LineSync TTL_Inx Specification Value Max. input frequency 16.5 Mhz Input voltage, absolute max. range min -0.5 V max 7.0 V Input voltage max. low 0.99 V Input voltage min. high.1 V Input current 10 µa Page

3 . Software and Hardware Installation Software Installation Install the software package SK91GigE-WIN onto the PC before attaching the camera. The SK91GigE-WIN software package contains the executable program SkLineScan, as well as class libraries, DLLs and samples for the operation and programming of CCD line scan cameras with a GigE Interface. The PC must have a high-performance video card and at least 1 GByte of RAM, depending on the size of acquired images, running or 64-bit Microsoft Windows 7, Vista or XP. The operating program SkLineScan depicts the signal from the CCD line scan camera on the computer screen as an oscilloscope display. Install the software package SK91GigE-WIN onto the PC before attaching the camera. The software installation starts automatically after inserting the SK91GigE-WIN CD in the CDROM drive. Manual execution can be started by using the setup.exe program in the root directory of the CD. For a network adapter in the PC with an Intel PRO/1000 chip then also install the High Performance Driver from the CD using the Driver Installation Tool". The Device Manager now has an entry for a "PRO/1000 Grabber Device". Hardware Installation Connect the power supply to the camera. Use a CAT6 cable to connect the camera to a GigE switch or directly to the GigE connection of the PC. For external synchronization, use the 1-pin SK904 cable for the trigger source. Network Adapters Any Gigabit Ethernet network adapter as a card or on the motherboard is suitable. For the best performance, a NIC with Intel PRO/1000 chip is recommended. PCIe adapters outperform PCI adapters. Network adapters that support Jumbo Frames outperform adapters with fixed packet-size frames. With two or more cameras working in parallel, the highest performance is achieved by simply multiplying up the single camera system, each with its own dedicated GigE network adapter in the PC. With independent pipelines, the full GigE bandwidth is available for each camera to use. Alternatively, two or more cameras can be plugged into a GigE switch, which is then connected to a single GigE connection in the PC, and all cameras must share the GigE bandwidth. While a mix of GigE switches and GigE LAN adapters is possible, all of the GigE LAN adapters must run in the same mode either with a High Performance Driver or using a standard network driver. The speed of the camera data transfer via Gigabit Ethernet can be up to 10 MBytes/s at a CPU load of only 1%. Optimizing non-intel PRO/1000 Network Adapters Most Gigabit network interface controllers allow the user to modify their parameters, such as Adapter Buffers and Jumbo Frames. These should be optimized during installation in the Advanced Properties of the Network Adapter if a non-intel PRO/1000 chip is present. Open the Device Manager and go to Advanced Properties of the Adapter Recommended optimization values: Receive Descriptors/Empfangsdescriptors = 048 Interrupt Moderation Rate (Interrupt-Drosselungsrate) = extreme Jumbo Frames = 9014 Byte Page

4 4. Camera Setup and Image Acquisition 4.1 SkLineScan The SkLineScan program recog nizes the connected line scan cameras automatically and orders the camera IDs according to the increasing values of their individual MAC addresses 1. 1 The oscillos cope display of the line scan signal, with zoom function, is an important tool for aligning the optical system. Integration time, gain and offset controls allow the online configuration of the camera. 4. Gain / Offset and Shading Correction The camera is shipped prealigned with gain and offset factory settings. The SK91GigE-WIN software package includes everything needed for a rapid set-up of the GigE camera, the configuration tool SkGigEconfig (see Section 5), as well as the software development kit (SDK) with DLLs and class libraries for the development of application software. Customized settings for gain / offset or shading correction can also be programmed using the SkLineScan software and are stored in the camera for future use, even after power loss. A Offset After blocking all light reaching the line sensor, bring the individual video signals close to zero using the R, G and B offset sliders (labelled A, B and C). The line signal should be just visible in the oscilloscope display. B Gain Now fully illuminate the sensor and move the R, G and B gain sliders to provide a slight overexposure for maximum signal clipping (55 for 8-bit, 4095 for 1-bit). GigE SK7500GTO B R G B C D area scans can easily be performed 4 by simply specifying the number of line scans to be integrated into the scan to produce a desired area scan. The zoom function allows the magnification of interesting areas 5 and full or partial images of the area scan, which can be stored as bitmaps. 4 C Shading Correction Shading correction is used to compensate for the potential sources of variation in the signal, whether caused by lens vignetting or variations in pixel sensitivity or illumination. A reference signal for the shading correction is obtained by taking an image of a plain white surface, so that each individual pixel can be compensated for algorithmically to provide a maximum overall intensity and an idealized flat signal. Alternatively, the R, G and B gain sliders can be used to regulate the signal. The shading correction memory (SCM) can be stored in the camera and activated or deactivated in the dialog according to demand. A Window Function - Region of Interest 5 The window function defines a freely programmable window (region of interest, ROI) on the line sensor. Only the pixel information within the ROI reaches the memory and, therefore, only these ranges are illuminated, reducing data volume and data processing for both line and picture acquisitions. The video data of the ROI is written left-bounded into the image buffer and the oscilloscope display in the SkLineScan program adjusts the ROI to the real pixel address of the signal window. For RGB pixel allocations in D imaging, see Section 6. Memory allocation designated for the ROI must be divisible by 8. Page 4

5 4. Synchronization 4.4 Thresholding (B/W cameras only) The various synchronization procedures allow images to be acquired either stepwise per line (LINE-SYNC) or per area (FRAME-SYNC) using an external trigger, according to the particular requirements of the customer or the image aquisition application. In free-run mode, the acquisition of one scan triggers the next scan immediately. When using external synchronization, the clock of an external TTL signal and the selected mode of synchronization determine the time of data acquisition. The LINE-SYNC modes are used for synchronization of single line scans and FRAME-SYNC triggers a full D scan. Line Sync Modes Free Run: Each line is acquired and the next scan is started automatically on completion of the previous line scan. Line Start: The triggered line is read out at the next line clock. The start and time of exposure are controlled internally by the camera and are not affected by the trigger. The exposure time is programmable and the trigger clock does not affect the exposure time. Exposure Start: A new exposure is started exactly at the time of triggering. The programmed exposure time is unaffected by the trigger clock. Exposure Active: The exposure time is controlled by the external trigger signal. Sync divider: Divides the external trigger frequency by a programmed integer. Only every n-th line is recorded. Thresholding is a special capability of cameras with a Gigabit Ethernet interface that offers an effective alternative to gray shade evalution and enumeration, assuming there is sufficient contrast available in the image. The development of thresholding is the successful outcome of an initiative to perform data reduction without information loss when monitoring changes in signal intensity. The thresholding process generates a binary signal, with data values below the threshold yielding 0 and those above yielding 1. Only the pixel addresses of the location and value (from high low or low high) of the threshold transition are transmitted with a line-end character (Runlength Encoding). Thresholding is particularly suitable for measuring widths or edge positions. The substantial complexities inherent in edge position determination have been reduced to quite simply masking the required pixel addresses. Data format: Bit 0...1: Bit 14: Bit 15: GigE SK7500GTF-XB 16-bit integer without a starting character pixel address of the signal transition 0 = transition from high low 1 = transition from low high 1 = line-end character Other thresholding features and possibilities include: Noise suppression filtering Subpixel resolution Frame Sync Mode The Frame Trigger synchronizes the acquisition of D area scans. The individual line scans in this area scan can be synchronized either in free run mode or triggered externally. The camera suppresses the data transfer until a falling edge of a TTL signal occurs at "FrameStart" input (useful for control by the breaching of a light barrier, for example). Timing: Frame Sync + trigger mode "LineStart" FrameStart ExtSync Video VideoValid Data transmission For Control Signal manipulation of Timing, see Section 7. Page 5

6 4.5 Continuous Imaging The SDK in the SK91GigE-WIN software package provides library functions that allow the user to allocate memory areas for an image acquisition. The GigE line scan camera then writes directly into these predefined memory areas, obviating any copying of the data from one area to another. The writing of camera data into memory can be performed either in a cyclical manner or after all of the buffers have been filled. This latter method is particularly useful for a sequence of images, up to a maximum of 56 individual images. The image sequence method allows the acquisition of extremely large images, circumventing the internal restriction of 64 MB and 168 lines per image. The user defines the appropriate memory size for the desired image size in virtual memory, which is then divided in up to 56 component parts. A sequence series is programmed by simply pointing to this buffer and the acquisition of the sequence images then results in the image data being collected to the desired size. Buffer 1 / Processing The ability to customize the memory allocation for the Gigabit Ethernet line scan cameras can be used for the continuous collection of the camera data into a User Buffer Queue. This speeds up operations as data must not be copied back and forth, freeing up the CPU for other activities, such as data evaluation or for controlling external devices. The writing of data into the User Buffer Queue is cyclical. Up to 56 buffer suballocations can be set according to the demands of the application. The minimum permitted size is exactly one line scan. The data in a previously filled buffer can be manipulated or evaluated while the camera is writing data into the next buffer. The user receives an event signal and the address of the buffer in the queue that was written to last. For the successful continuous evaluation of camera data in the two buffers, without loss of data, the evaluation of the first buffer must be completed after the illumination of n lines, at the latest. When more than two buffers are allocated and there is a time delay caused by the manipulation of data from one buffer then the time delay can be recovered by the rapid utilization of the data in the next or subsequent buffers. Thus, there are no time limits or restrictions when performing continuous acquisition and data manipulation tasks. Initialization DMA initialisieren scans lines= n, = done= n, done 0 = 0 Processing Auswerten Buffer / Acquisition Continuous ErfassungGrab User Ring Buffer DMA-Ringspeicher 0 n done+1 n Zeile n lines done+1 Line clock n n n 4n Acquisition 1 Acquisition Processing 1 Processing Image Counter done = e.g. Camera SK4096GPD-L Image Processing Start buffer 0 buffer 1 buffer buffer buffer 4 buffer 5 buffer 6 buffer 7 Sequence acquired Image dimensions: 4096 x 768 pixels Image size: 18 MByte Number of buffers: 8 Buffer size : 16 MByte Image memory 18 MByte For RGB pixel allocations in D imaging, see Section 6. For Control Signal manipulation of Timing, see Section 7. Page 6

7 5. SkGigEconfig and Serial Commands The supplied config program SkGigEconfig can be used to modify the gain, offset or pixel frequency settings using the sliders or by sending camera control commands directly. Current gain, offset, pixel frequency or specific product information can also be read from the camera using the get serial commands. Examples of serial commands are listed in the Set (left) and Get (right) tables, respectively. Set Commands Read Commands Set Operation Description Goooo<CR> gain 1 (Red odd) 0-0 db Boooo<CR> gain (Red even) 0-0 db Hoooo<CR> gain (Green odd) 0-0 db Joooo<CR> gain 4 (Green even) 0-0 db [ oooo<cr> gain 5 (Blue odd) 0-0 gain 6 (Blue even) 0-0 db Oppp<CR> off1 (Red odd) Pppp<CR> off (Red even) Qppp<CR> off (Green odd) Uppp<CR> off4 (Green even) ] ppp<cr> off5 (Blue odd) _ppp<cr> off6 (Blue even) C60<CR> camera Clock: 60 MHz C10<CR> camera Clock: 10 MHz T0<CR> test pattern off T1<CR> test pattern on (turns off with power off) T<CR> shading correction on T<CR> auto program Shading Correction/SCM on T4<CR> copy Flash Memory to SCM T5<CR> save SCM to flash memory T6<CR> video out = SCM data M0<CR> Trigger Mode0: internal all Lines M1<CR> Trigger Mode5: external, next line (J) M<CR> Trigger Mode0: intern all lines, set max line rate M<CR> Pleora sync modes M5<CR> Trigger Mode5: extern SOS, all Lines (J) Ayyyyy <CR> SCM address (yyyyy = 0-799) Dxxxx<CR> SCM data (0-4095) + increment SCM address Wxxxx<CR> line frequency ( Hz) Xyyyyy<CR> exposure time (yyyyy = µs) Vyyyyy<CR> extern Sync divider (yyyyy = 1-767) Yppp<CR> set Sync control (ppp = 0-55) Range of values: oooo = , ppp = yyyyy = 5 digits integer value as ASCII Return confirmation: 0 = OK, 1 = not OK Request Return Description K<CR> SK800GJRC-XC SK type number R<CR> Rev.1 Revision number S<CR> SNr0016 Serial number I1<CR> VCC: yyyyy VCC (1=10 mv) I<CR> VDD: yyyyy VDD (1=10 mv) I<CR> moo: yyyyy mode of operation I4<CR> CLo: yyyyy clock low frequency (MHz) I5<CR> CHi: yyyyy clock high frequency (MHz) I6<CR> Ga1: yyyyy gain 1 I7<CR> Ga: yyyyy gain I8<CR> Of1: yyyyy offset 1 I9<CR> Of: yyyyy offset I10<CR> Ga: yyyyy gain I11<CR> Ga4: yyyyy gain 4 I1<CR> Of: yyyyy offset I1<CR> Of4: yyyyy offset 4 I15<CR> Ga5: yyyyy gain 5 I16<CR> Ga6: yyyyy gain 6 I17<CR> Of5: yyyyy offset 5 I18<CR> Of6: yyyyy offset 6 I19<CR> Tab: yyyyy video channels I0<CR> CLK: yyyyy selected clock freq (MHz) I1<CR> ODF: yyyyy selected output data format I<CR> TRM: yyyyy selected trigger mode I<CR> SCO: yyyyy shading correction on/off I4<CR> Exp: yyyyy exposure time (µs) I5<CR> mix: yyyyy min. exposure time (µs) I6<CR> LCK: yyyyy line frequency (Hz) I7<CR> maz: yyyyy max. line frequency (Hz) I8<CR> TSc: yyyyy Sync divider I9<CR> SyC: yyyyy Sync control Page 7

8 6. RGB Sensors: D Imaging and Pixel Allocation Triple line sensors have separate sensor lines for the primary colors red, green and blue and can achieve extremely high optical resolutions. The SK800GJRC-XC color line scan camera has a triple line sensor with 7600 pixels each for red, green and blue. The sensors are directly adjacent, providing an inter-sensor distance of 9. µm equivalent to the size of a pixel. 9. µm The co lor information originating from the different parts of the object is transmitted in parallel and stored in the PC before being correctly reallocated. Line 0 1 Pixel line Raw Data R G B R G B R G B R G B R G B R G B R G B R G B R G B R G B R G B R G B... Allocation of color information 9. µm RED GREEN BLUE RED GREEN BLUE Signal display - RGB splitting A two-dimensio nal color image is generated by moving the object or the camera, ensuring that the sensor properties, the travel direction and speed are all accounted for: object velocity = pixel width magnification exposure time Triple line sensors require a precise synchronous translation of the object for the correct allocation of pixels A. When these conditions are not met then images with co lor convergence ab er rations are generated B. A B Monochrome font pattern A line synchronous object transport B asynchronous transport of the object causes color convergence aberration During object travel at a translation rate of one pixel per clock pulse, all color information is acquired within clock cycles. An object point reaches the red line sensor first, followed immediately by the green, by which time the red sensor is collecting the next object information, and finally the blue line sensor, by which time the green and red sensors are collecting subsequent slices of object information, respectively. Page 8

9 7. Control Signals and Timing Diagram SOS CC1 CCLK STROBE LVAL R[0-7] 458 Clock Cycles 7600 Clock Cycles 6 Clock Cycles 15 ns G[0-7] B[0-7] Video intern for Red, Green, Blue, odd and even Page 9

10 8. Sensor Performance Specifications Producer: Type: Data source: Sony ILX146K 7600-pixel 4-line CCD Linear Sensor (Color) - Technical Data Sheet Electro-optical Characteristics Page 10

11 Page 11

12 Block Diagram Page 1

13 9. Dimensions Casing group: CG7 CCD line scan camera, digital Distance to sensor: 10.4 mm Data Connector: Mini-D ribbon, female 6-pin Power Connector: Hirose series HR10A, female 6-pin ,8,66 9,8,66 11, sensor sensor 8 11, /M4 50/M4 A M7x0.75 M7x /M4 10 B M7x0.75-6H -6 DEEP -6 DEEP M4x0.7-6HM4x0.7-6H 8 8 M4x0.7-6HM4x0.7-6H C 1,5 15 1,5 15 Focus adapter FA6XC-S55 51 mm + 8 mm Focus adapter with variable length for with adapter M55x D SK800GJRC-XC. Compatible with Lens adapter AC46-55 and Extension ring ZR Ø 71.5 f8 M55x0.75 E Page 1 Bearb. Gepr. Norm Allgemeintoleranz ISO f Datum Name Maßstab: 1: SK800GJRC_XC_S with M7x0.75-Mount F

14 10. Line Scan Camera Fundamentals Line scan cameras from Schäfter+Kirchhoff are supplied factory-preset for the particular application, with optional accessories and appropriate software for parameterization of the camera or for optimizing signal acquisition. The advantages and constraints of the technology are described below and some essential aspects of sensor alignment, lens focussing and signal optimization are presented Features and Characteristics Pixel 1 CCD Sensor GigE SK7500GTO Object structure A charge-coupled device is a linear array designed for moving discrete electrical charges from one element of the array to the next by successively applying a voltage to each element in turn. The discrete charge packets emanating from the end of the linear array are converted into a voltage and digitized for further transmission. A line scan signal is produced by moving the object to be imaged in a trajectory perpendicular to the camera sensor. By synchronizng data acquisition, high frequencies and resolutions are achieved. The choice of line scan camera is primarily determined by the customer application requirements, which influence sensor length, pixel number and line scan frequency see Imaging Definitions, below. Imaging Definitions Exposure Period and Integration Time The illumination cycle of a line scan sensor, of a particular length and number of pixels, for a set period of time is designated the exposure period. Within a single exposure period, the integration time is the duration designated for signal accumulation of charges by the sensor. In continuous mode, the next exposure cycle is simply begun at the time of read-out of the previous exposure and, so, the durations of exposure period and integration time are identical. Cameras with integration control are capable of curtailing the integration time within an exposure period (emulating a shutter mechanism). Other custom features can be chosen, such as specialized or filtered illumination, choice of color or monochrome line sensors as well as type of interface, with either GigE Vision TM, Gigabit Ethernet, LVDS, CameraLink or USB.0 interfaces available for data output. The oscilloscope display facility of the supplied software is responsive in realtime, and the zoom function can be used to highlight an area of interest. The oscilloscope display is ideally suited for parameterizing the camera, for evaluating object illumination, for focussing the image or for aligning the line scan camera correctly see Section 10. Alignments and Adjustments. A line scan camera D area scan can easily be performed by simply specifying the number of line scans to be integrated. Pixel and Line Scan Frequencies The pixel frequency for an individual sensor is the rate of charge transfer from pixel to pixel and its ultimate conversion into a signal. The minimum exposure period of a sensor is the minimum time required for the read-out of a whole line scan and is dependent on the maximum pixel frequency and the number of pixels (plus a sensor-dependent overhead of passive pixels). The line scan frequency is inversely proportional to exposure period. During the time the charges from a finished line scan are read out, the next line scan is being exposed. Thus, the minimum exposure period determines the maximum line scan frequency. Our considerable experience in line scan camera design and software production allows us to get the best possible imaging performance within the constraints of the technology. Potential problems are simply designed out or an intrinsic constraint is tuned away according to circumstance. For example, illumination over-exposure of the sensor causes blooming and signal blur or loss, from charge leakage across pixels. Blooming can be either designed out (antiblooming) or cut by reducing the integration time or lens aperture. Similarly, gain and offset tuning can increase signal-to-noise ratios, while shading correction negates any problems of pixel variability, lens vignetting or inhomogeneous illumination, whether initially present or not. Optical Resolution The optical resolution of a line scan camera is determined primarily by the number of pixels in the linear sensor and secondarily by their size and spacing, the inter-pixel distance. Currently available line scan cameras have up to pixels, ranging from 4 to 14 µm in size and spacing, for sensors up to 56 mm in length and line scan frequencies up to 8 khz. During a scanning run, the effective resolution perpendicular to the line scan camera is determined by the velocity of the scan and by the line scan frequency, i.e. the number of line scans per second. Data Reduction and Acquisition Acceleration Thresholding (B/W cameras only) The thresholding process generates a binary signal from the gray scale data, with values below the threshold yielding 0 and those above yielding 1. Only the pixel addresses of the location and threshold transition (from high low or low high) are transmitted, reducing data throughput. Thresholding is particularly appropriate for measuring widths or edge positions, by simply masking the required pixel addresses. GigE SK7500GTF-XB Region of Interest A freely programmable window (region of interest, ROI) can be applied to the line sensor so that only the pixel information within the ROI can reach the memory. By only illuminating these ranges, data volume and data processing is accelerated for both line and area scan acquisitions. Constraint: the ROI memory allocation must be divisible by 8. Page 14

15 10. Alignments and Adjustments Sensor Alignment For linear illumination sources, rotating the line sensor results in asymmetric vignetting. The camera and illumination optics can be aligned optimally by monitoring the object illumination using the oscilloscope display. Sensor and optics rotated in apposition A and aligned B. A B Integration Time and Aperture Optimization The line scan signal is optimum when the signal from the brightest region of the object corresponds to 95% of the maximum gain. Full use of the digitalization depth (55 at 8-bit, 4096 at 1-bit) provides an optimum signal sensitivity and avoids over-exposure (and blooming). The range of intensity distribution of the line scan signal is affected by the illumination intensity, the aperture setting and the camera integration time. Conversely, the aperture setting influences the depth of field as well as the overall quality of the image and the perceived illumination intensity. A A camera signal exhibiting insufficient gain: the integration time is too short as only about 50% of the B/W gray scale is used. B Optimized gain of the camera signal after increasing the integration time, by a factor of 4, to 95% of the available scale. A B Gain / Offset and Shading Correction Cameras are shipped prealigned with gain and offset factory settings, although they can be customized using the SkLineScan software. A Offset. After blocking all light reaching the line sensor, the video signals are adjusted to zero using the offset sliders. The line signal should be just visible at the bottom of the oscilloscope display. B Gain. The sensor is fully illuminated and the gain sliders adjusted to provide a close to maximum signal intensity (55 for 8-bit or 4095 for 1-bit) and superimposed signals for each camera or RGB channel. C Shading Correction. Shading correction, white balance or flat-field compensation are all related techniques that automatically compensate for any variation in pixels, lens vignetting or inhomogeneity in the illumination, etc, whether initially present or not. All lenses show some vignetting as a function of the field angle (collectively, the relationship between sensor and focal lengths and magnification). Hence, even with homogeneous object illumination, the image signal intensity decreases with increasing image height. A reference signal for shading correction, for example, is obtained by taking an image of a diffuse white surface, followed by algorithmic compensation of each pixel to provide a maximum overall intensity. Many alternative solutions are available, such as using the R, G and B gain sliders directly to superimpose the individual channels. Corrected parameter settings can be stored within the non-volatile memory of the camera and are retained for subsequent use even after a complete shutdown. C B A Lens Focussing The oscilloscope display can also be used to focus a line scan camera system by using the variations in edge steepness at dark/bright transitions observed as modulations in the zoomed line scan signal. Initial focussing is performed with a fully opened aperture (smallest depth of field and largest sensitivity to focus adjustment). The integration time can also be reduced to provide a sufficiently sensitive, low amplitude signal. A Out of focus: edges are indistinct, signal peaks blurred with low density modulation B Optimal focus: dark-bright transitions have sharp edges, highly modulated signal peaks with high frequency density variations A B Page 15

16 11. Warranty 1. Accessories This manual has been prepared and reviewed as carefully as possible but no warranty is given or implied for any errors of fact or in interpretation that may arise. If an error is suspected then the reader is kindly requested to inform us for appropriate action. The circuits, descriptions and tables may be subject to and are not meant to infringe upon the rights of a third party and are provided for informational purposes only. The technical descriptions are general in nature and apply only to an assembly group. A particular feature set, as well as its suitability for a particular purpose, is not guaranteed. The warranty period for the CCD line scan camera when used for the purpose for which it was intended is 4 months. The warranty is immediately void on inappropriate modification, use or damage. EC Declaration of Conformity This product satisfies the requirements of the EC directive 89/6/EEG as well as DIN EN 616. Mounting bracket SK5105-G Order Code Warp-resistant construction for the mounting of the CCD line scan camera Clamp set SK5101 Order Code to lock the CCD line scan camera in desired position CAT6 network cable Shielded CAT6 patch cable, halogen-free, both ends with RJ45 connectors for Gigabit Ethernet CAT6. Order Code = m cable length 5 = 5 m (standard) x = length of choice (up to 100 m) Cable for external synchro nization BNC coaxial cable with Hirose connector HR10A, female 1-pin SK904. Order Code = m cable length 5 = 5 m (standard) x = length of choice Power supply cable SK Shielded cable with male 6-pin Lumberg SV60 and female 6-pin Hirose HR10A connectors SK MF Order Code MF = connector (male/female) 0. = 0. m cable length 1.5 = 1.5 m (standard) Power Supply: PS Order Code Input: V AC, 50/60 Hz, 0.8 A -pin input connection (IEC 0) Output: 5 V DC/.5 A 15 V DC/0.5 A, -15 V DC/0. A output connector: Lumberg KV60, female 6-pin, length 1 m Software: SK91GigE-WIN * Order Code SK91GigE-LV ** SkLineScan operating program for camera control. SDK with examples, DLLs and C++ class library. * Windows 7 (/64 bit) / Vista (/64) / XP / 000 ** LabVIEW VI library SK800GJRC-XC Lenses: high resolution enlarging and macro lenses high speed photo lenses lenses with additional locking bridge for locking of focus and aperture setting Adapter: Lens adapter AOC-... for fitting photo lenses onto the CCD line scan camera Focus adapter FA-... for fitting enlarging or macro lenses Kieler Str. 1, 55 Hamburg, Germany Tel: Fax: info@sukhamburg.de