Physics in Modern Medicine Fall 2010
|
|
- Margaret Verity Hicks
- 5 years ago
- Views:
Transcription
1 Physics in Modern Medicine Fall 2010 Homework #3 Chapter 3 Lasers in Medicine Questions Q3.1 Absorption in melanin increases with decreasing wavelength, and has a maximum, according to figure 3.23 in the UV, but will absorb the green light of an Argon laser (488nm) as well as the blue/green (514) of the Argon. The absorption spectrum will dictate which laser is appropriate for treatment. Q3.5 Since the chief pigment in the endometrial tissue is blood, a good choice of laser would be one that is in the blue portion of the spectrum and one that would be inappropriate would be a laser whose output is in the red portion of the spectrum. An appropriate choice for the laser would be something in the nm range, say an Argon laser or maybe a copper vapor. An inappropriate choice for the laser would be lasers whose wavelength is in the 600nm and larger range, say He-Ne, Krypton, ruby and any IR laser. Q3.9 Eximer lasers, which are ultraviolet lasers, are used in photorefractive surgery because the cornea is transparent to any visible light, such as that in the argon laser. The cornea is a good absorber of UV radiation. The retina on the other hand has many blood vessels and to target these in a surgery one would want the argon laser since it operates in the blue-green portion of the EM spectrum and would be preferentially absorbed by the red blood cells here. Problems P3.5 a) To achieve a power density of 80 milliwatts/cm 2 with a 1 watt CW laser, you would need a spot size given by (Eq. 3.7): I = P/(πr 2 ) Where I = power density in watts/cm 2, P = power in watts, and r = spot radius in cm. Solving for the spot radius, r, we get:
2 So a spot with a radius of 2 cm would be appropriate. b) The exposure time would be given by: T = F / I = (100 J/cm 2 )/( 80 milliwatts/cm 2 ) = (100 J/cm 2 )/( 80 x 10 3 watts/cm 2 ) = (100 J/cm 2 )/( 80 x 10 3 J/s /cm 2 ) = (100/0.080) sec (1 min /60 sec) = 21 min This is within reasonable bounds for a therapeutic procedure. c) The goals would be to maximize absorption for the photosensitizer, in this case phthalocyanine, and at the same time to minimize hemoglobin absorption, which is not specific to tumors. Since phthalocyanine has an absorption peak and hemoglobin absorbs relatively weakly at the region between 600 to 720 nm, the red gold vapor laser (630 nm), Krypton laser (676.4 nm), and dye laser operating in this wavelength range would be reasonable choices. The heliumneon laser has a good match, but in fact the powers achievable tend to be too low for this use. The ruby laser is a similarly good wavelength match, but the pulsed operation is not desirable in this application. d) The reason lasers are a good choice involves both their spatial coherence, necessary because of the need for relatively high power densities over a small region of tissue, and their temporal coherence, which is important to guarantee that the power density delivered is concentrated at the absorption peak of the photosensitizer, while avoiding high levels of absorption by other body tissues, such as blood. The very similar absorption properties of hemoglobin and many photosensitizers especially make the latter criterion highly important. Chapter 4 Diagnostic Ultrasound Questions Q4.3 Low frequency foghorns have long wavelengths. These long wavelengths, when they disperse through space, can envelope the ship so that anyone on the ship can hear the sound. If high frequency sound were used, with a
3 shorter wavelength, then you would only target perhaps, a small area of the ship and the ship may not be aware of the danger if no one hears the sound. Q4.4 Increasing the frequency may improve your resolution, but the penetration depth of the sound into the sample would go to zero. The half intensity depth is inversely related to the frequency. As the frequency approaches infinity, the penetration depth approaches zero. Q4.5 Miscalibration of the US scanner will produce distortions in the US image. To correct for miscalibrations the sonographer or technician would use test samples, or phantoms for calibration. Other effects that will cause distortions are refraction of the sound waves as the waves pass from one material into another and reverberations. Refraction produces echoes that are displaced from the expected path. Refraction can produce double images and there s not much to fix this problem. Reverberations are multiple high-intensity echoes from two strongly reflecting interfaces. Acoustic shadowing is another problem. US scanners compensate for the fact that the US pulse intensity decreases with increasing depth into the sample by artificially increasing the brightness. Acoustic shadows are created if a strong absorbing or very reflective surface is encountered by the US wave and the scanner software over compensates. Problems P4.1 a) We will use the average speed of sound in soft tissue here, v s = 1540 m/s, and the equations given in Chapter 4 relating the wavelength to frequency for a given medium, and hence speed of sound: Such a frequency is actually used in ultrasound imaging, and it would be adequate to resolve fairly small features of the heart or a large abdominal organ, for example. b) For this second calculation, we use the value of the speed of sound in air, instead: 344 m/s: Note that the wavelength associated with a particular frequency depends strongly upon the medium in which the sound wave travels, because of the very different values of the speed of sound.
4 P4.2 a) We wish to have an ultrasound wavelength of 0.50 mm in soft tissues, for which the speed of sound is v s = 1540 m/s. This requires us to solve Eq. 4.1 for the frequency: This is indeed in the range of frequencies used for abdominal and obstetrical ultrasound imaging. b) Now we are asked to solve for the speed of sound, given the frequency and wavelength of a wave in the material as 2.0 MHz and 1.75 mm. Using Eq. 4.1, we have: Although it was not required for the answer to this problem, you may have noted that 3500 m/s is the speed of sound in bone (Table 4.2). P4.3 a) We can apply Eq. 4.8 to translate the time it takes to send and receive echoes into distance measurements. The time for the pulse to travel to and reach the interface is given as 20 ms = s, so this corresponds to a distance of: Here we ve used the book s estimate of 1540 m/s as an average travel time for ultrasound within the body. Even in such a short amount of time (about onesixth of a second), ultrasound waves travel a very great distance. b) If the interfaces are ΔD = 5.0 cm apart, we can again use the equation from a) and the value of the speed of sound to estimate how much time would elapse between the echoes. We first need to note that the extra distance traveled by the echo from the second interface (i.e., the one farthest from the transducer) will be 10.0 cm (0.100 m), because the second pulse must travel to the interface (5.0 cm) and travel an extra 5.0 cm on its return trip. We can then compute the extra time for the second echo pulse to reach the transducer from: t = 2 ΔD/ vs = 2 (5.0 cm) / Δ = m /1540 m/s = s
5
Chapter 4. Pulse Echo Imaging. where: d = distance v = velocity t = time
Chapter 4 Pulse Echo Imaging Ultrasound imaging systems are based on the principle of pulse echo imaging. These systems require the use of short pulses of ultrasound to create two-dimensional, sectional
More information12/26/2017. Alberto Ardon M.D.
Alberto Ardon M.D. 1 Preparatory Work Ultrasound Physics http://www.nysora.com/mobile/regionalanesthesia/foundations-of-us-guided-nerve-blockstechniques/index.1.html Basic Ultrasound Handling https://www.youtube.com/watch?v=q2otukhrruc
More informationMicropulse Duty Cycle. # of eyes (20 ms) Total spots (200 ms)
Micropulse Duty Cycle Total spots (2 ms) # of eyes (2 ms) Total spots (2 ms) % 269 44 3 47% 9 4 4 25% 3 5 4 4 5% 2 4 3 5 2% 5 2 NA NA 9% 2 4 6% NA NA 57 2 5% 4 5 6 3 3% 39 5 35 5 # of eyes (2 ms) Supplemental
More informationThe physics of ultrasound. Dr Graeme Taylor Guy s & St Thomas NHS Trust
The physics of ultrasound Dr Graeme Taylor Guy s & St Thomas NHS Trust Physics & Instrumentation Modern ultrasound equipment is continually evolving This talk will cover the basics What will be covered?
More informationUltrasound Beamforming and Image Formation. Jeremy J. Dahl
Ultrasound Beamforming and Image Formation Jeremy J. Dahl Overview Ultrasound Concepts Beamforming Image Formation Absorption and TGC Advanced Beamforming Techniques Synthetic Receive Aperture Parallel
More informationused to diagnose and treat medical conditions. State the precautions necessary when X ray machines and CT scanners are used.
Page 1 State the properties of X rays. Describe how X rays can be used to diagnose and treat medical conditions. State the precautions necessary when X ray machines and CT scanners are used. What is meant
More informationFigure 1. Relative intensity of solar energy of different wavelength at the earth's surface.
Spectrum of light from the sun: Fig.1 Figure 1. Relative intensity of solar energy of different wavelength at the earth's surface. Properties of light 1-The speed of light changes when it goes from one
More informationLight has some interesting properties, many of which are used in medicine:
LIGHT IN MEDICINE Light has some interesting properties, many of which are used in medicine: 1- The speed of light changes when it goes from one material into another. The ratio of the speed of light in
More informationThe Physics of Echo. The Physics of Echo. The Physics of Echo Is there pericardial calcification? 9/30/13
Basic Ultrasound Physics Kirk Spencer MD Speaker has no disclosures to make Sound Audible range 20Khz Medical ultrasound Megahertz range Advantages of imaging with ultrasound Directed as a beam Tomographic
More informationLaser Safety & the Human Eye Recall the human eye is a simple single lens system Crystalline lens provide focus Cornea: outer surface protection
Laser Safety & the Human Eye Recall the human eye is a simple single lens system Crystalline lens provide focus Cornea: outer surface protection Iris: control light Retina: where image is focused Note
More informationLesson 02: Sound Wave Production. This lesson contains 24 slides plus 11 multiple-choice questions.
Lesson 02: Sound Wave Production This lesson contains 24 slides plus 11 multiple-choice questions. Accompanying text for the slides in this lesson can be found on pages 2 through 7 in the textbook: ULTRASOUND
More informationPhysics of ultrasound
1 Physics of ultrasound Basic principles Nature of ultrasound Sound = longitudinal, mechanical wave particles move parallel to direction of travel Audible sound < 20 khz Ultrasound > 20 khz Sound cannot
More informationWinter College on Optics: Trends in Laser Development and Multidisciplinary Applications to Science and Industry February 2013
2443-28 Winter College on Optics: Trends in Laser Development and Multidisciplinary Applications to Science and Industry 4-15 February 2013 Laser Safety V. Lakshminarayanan University of Waterloo Canada
More informationINTRODUCTION TO LASERS TECHNOLOGY EDUCATION SCARSDALE MIDDLE SCHOOL
INTRODUCTION TO LASERS TECHNOLOGY EDUCATION SCARSDALE MIDDLE SCHOOL Many of the pictures for this LASER presentation came from www.howstuffworks.com. LASER PRESENTATION 2 LASER Originally LASER was an
More informationLaser processing of materials. Laser safety
Laser processing of materials Laser safety Prof. Dr. Frank Mücklich Dr. Andrés Lasagni Lehrstuhl für Funktionswerkstoffe Sommersemester 2007 Contents: LASER Safety Laser-tissue interaction Type of interaction
More informationUltrasound Physics. History: Ultrasound 2/13/2019. Ultrasound
Ultrasound Physics History: Ultrasound Ultrasound 1942: Dr. Karl Theodore Dussik transmission ultrasound investigation of the brain 1949-51: Holmes and Howry subject submerged in water tank to achieve
More informationLesson 06: Pulse-echo Imaging and Display Modes. These lessons contain 26 slides plus 15 multiple-choice questions.
Lesson 06: Pulse-echo Imaging and Display Modes These lessons contain 26 slides plus 15 multiple-choice questions. These lesson were derived from pages 26 through 32 in the textbook: ULTRASOUND IMAGING
More informationWaves, Sound and Light. Grade 10 physics Robyn Basson
Waves, Sound and Light Grade 10 physics Robyn Basson Heartbeat Flick in hose pipe What is a pulse? A single disturbance that moves through a medium. Stone in water Other? moving Transverse pulse: A pulse
More informationLesson 06: Pulse-echo Imaging and Display Modes. This lesson contains 22 slides plus 15 multiple-choice questions.
Lesson 06: Pulse-echo Imaging and Display Modes This lesson contains 22 slides plus 15 multiple-choice questions. Accompanying text for the slides in this lesson can be found on pages 26 through 32 in
More informationLASERS. & Protective Glasses. Your guide to Lasers and the Glasses you need to wear for protection.
LASERS & Protective Glasses Your guide to Lasers and the Glasses you need to wear for protection. FACTS Light & Wavelengths Light is a type of what is called electromagnetic radiation. Radio waves, x-rays,
More informationLaser Induced Damage Threshold of Optical Coatings
White Paper Laser Induced Damage Threshold of Optical Coatings An IDEX Optics & Photonics White Paper Ronian Siew, PhD Craig Hanson Turan Erdogan, PhD INTRODUCTION Optical components are used in many applications
More informationChapter 20 Human Vision
Chapter 20 GOALS When you have mastered the contents of this chapter, you will be able to achieve the following goals: Characterize the physical parameters that are significant in human vision. Visual
More informationPhysics of Ultrasound Ultrasound Imaging and Artifacts รศ.นพ.เดโช จ กราพาน ชก ล สาขาหท ยว ทยา, ภาคว ชาอาย รศาสตร คณะแพทยศาสตร ศ ร ราชพยาบาล
Physics of Ultrasound Ultrasound Imaging and Artifacts รศ.นพ.เดโช จ กราพาน ชก ล สาขาหท ยว ทยา, ภาคว ชาอาย รศาสตร คณะแพทยศาสตร ศ ร ราชพยาบาล Diagnosis TTE TEE ICE 3D 4D Evaluation of Cardiac Anatomy Hemodynamic
More informationInteraction of Sound and. logarithms. Logarithms continued. Decibels (db) Decibels (db) continued. Interaction of Sound and Media continued
Interaction of Sound and Media continued Interaction of Sound and Media Chapter 6 As sound travels through a media and interacts with normal anatomical structures its intensity weakens through what is
More informationUses of Electromagnetic Waves
Uses of Electromagnetic Waves 1 of 42 Boardworks Ltd 2016 Uses of Electromagnetic Waves 2 of 42 Boardworks Ltd 2016 What are radio waves? 3 of 42 Boardworks Ltd 2016 The broadcast of every radio and television
More informationIntroduction. Chapter 16 Diagnostic Radiology. Primary radiological image. Primary radiological image
Introduction Chapter 16 Diagnostic Radiology Radiation Dosimetry I Text: H.E Johns and J.R. Cunningham, The physics of radiology, 4 th ed. http://www.utoledo.edu/med/depts/radther In diagnostic radiology
More informationUltrasound Bioinstrumentation. Topic 2 (lecture 3) Beamforming
Ultrasound Bioinstrumentation Topic 2 (lecture 3) Beamforming Angular Spectrum 2D Fourier transform of aperture Angular spectrum Propagation of Angular Spectrum Propagation as a Linear Spatial Filter Free
More informationFigure 1. monkeybusinessimages/istock/thinkstock
Q1.Lenses can be used to correct visual defects. Figure 1 shows a child wearing glasses. Wearing glasses allows a lens to correct a visual defect. Figure 1 monkeybusinessimages/istock/thinkstock (a) Figure
More informationP6 Quick Revision Questions
P6 Quick Revision Questions H = Higher tier only SS = Separate science only Question 1... of 50 Define wavelength Answer 1... of 50 The distance from a point on one wave to the equivalent point on the
More informationUnit 1.5 Waves. The number waves per second. 1 Hz is 1waves per second. If there are 40 waves in 10 seconds then the frequency is 4 Hz.
Unit 1.5 Waves Basic information Transverse: The oscillations of the particles are at right angles (90 ) to the direction of travel (propagation) of the wave. Examples: All electromagnetic waves (Light,
More informationWave Behavior and The electromagnetic Spectrum
Wave Behavior and The electromagnetic Spectrum What is Light? We call light Electromagnetic Radiation. Or EM for short It s composed of both an electrical wave and a magnetic wave. Wave or particle? Just
More informationSection 1: Sound. Sound and Light Section 1
Sound and Light Section 1 Section 1: Sound Preview Key Ideas Bellringer Properties of Sound Sound Intensity and Decibel Level Musical Instruments Hearing and the Ear The Ear Ultrasound and Sonar Sound
More informationThe Special Senses: Vision
OLLI Lecture 5 The Special Senses: Vision Vision The eyes are the sensory organs for vision. They collect light waves through their photoreceptors (located in the retina) and transmit them as nerve impulses
More informationCOMPONENTS OF OPTICAL INSTRUMENTS. Chapter 7 UV, Visible and IR Instruments
COMPONENTS OF OPTICAL INSTRUMENTS Chapter 7 UV, Visible and IR Instruments 1 Topics A. GENERAL DESIGNS B. SOURCES C. WAVELENGTH SELECTORS D. SAMPLE CONTAINERS E. RADIATION TRANSDUCERS F. SIGNAL PROCESSORS
More informationCOMPONENTS OF OPTICAL INSTRUMENTS. Topics
COMPONENTS OF OPTICAL INSTRUMENTS Chapter 7 UV, Visible and IR Instruments Topics A. GENERAL DESIGNS B. SOURCES C. WAVELENGTH SELECTORS D. SAMPLE CONTAINERS E. RADIATION TRANSDUCERS F. SIGNAL PROCESSORS
More informationScience 8 Unit 2 Pack:
Science 8 Unit 2 Pack: Name Page 0 Section 4.1 : The Properties of Waves Pages By the end of section 4.1 you should be able to understand the following: Waves are disturbances that transmit energy from
More informationElectromagnetic Waves
Electromagnetic Waves What is an Electromagnetic Wave? An EM Wave is a disturbance that transfers energy through a field. A field is a area around an object where the object can apply a force on another
More informationLaser and LED retina hazard assessment with an eye simulator. Arie Amitzi and Menachem Margaliot Soreq NRC Yavne 81800, Israel
Laser and LED retina hazard assessment with an eye simulator Arie Amitzi and Menachem Margaliot Soreq NRC Yavne 81800, Israel Laser radiation hazard assessment Laser and other collimated light sources
More informationVision 1. Physical Properties of Light. Overview of Topics. Light, Optics, & The Eye Chaudhuri, Chapter 8
Vision 1 Light, Optics, & The Eye Chaudhuri, Chapter 8 1 1 Overview of Topics Physical Properties of Light Physical properties of light Interaction of light with objects Anatomy of the eye 2 3 Light A
More informationPHYSICS. Chapter 35 Lecture FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E RANDALL D. KNIGHT
PHYSICS FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E Chapter 35 Lecture RANDALL D. KNIGHT Chapter 35 Optical Instruments IN THIS CHAPTER, you will learn about some common optical instruments and
More informationNote 2 Electromagnetic waves N2/EMWAVES/PHY/XII/CHS2012
ELECTROMAGNETIC SPECTRUM Electromagnetic waves include visible light waves, X-rays, gamma rays, radio waves, microwaves, ultraviolet and infrared waves. The classification of em waves according to frequency
More informationLlIGHT REVIEW PART 2 DOWNLOAD, PRINT and submit for 100 points
WRITE ON SCANTRON WITH NUMBER 2 PENCIL DO NOT WRITE ON THIS TEST LlIGHT REVIEW PART 2 DOWNLOAD, PRINT and submit for 100 points Multiple Choice Identify the choice that best completes the statement or
More informationObserving Microorganisms through a Microscope LIGHT MICROSCOPY: This type of microscope uses visible light to observe specimens. Compound Light Micros
PHARMACEUTICAL MICROBIOLOGY JIGAR SHAH INSTITUTE OF PHARMACY NIRMA UNIVERSITY Observing Microorganisms through a Microscope LIGHT MICROSCOPY: This type of microscope uses visible light to observe specimens.
More informationChapter 36: diffraction
Chapter 36: diffraction Fresnel and Fraunhofer diffraction Diffraction from a single slit Intensity in the single slit pattern Multiple slits The Diffraction grating X-ray diffraction Circular apertures
More informationELECTROMAGNETIC WAVES AND THE EM SPECTRUM MR. BANKS 8 TH GRADE SCIENCE
ELECTROMAGNETIC WAVES AND THE EM SPECTRUM MR. BANKS 8 TH GRADE SCIENCE ELECTROMAGNETIC WAVES Do not need matter to transfer energy. Made by vibrating electric charges. When an electric charge vibrates,
More informationElectromagnetic Spectrum
Electromagnetic Spectrum Wave - Review Waves are oscillations that transport energy. 2 Types of waves: Mechanical waves that require a medium to travel through (sound, water, earthquakes) Electromagnetic
More informationVision. The eye. Image formation. Eye defects & corrective lenses. Visual acuity. Colour vision. Lecture 3.5
Lecture 3.5 Vision The eye Image formation Eye defects & corrective lenses Visual acuity Colour vision Vision http://www.wired.com/wiredscience/2009/04/schizoillusion/ Perception of light--- eye-brain
More informationVisibility of Detail
Visibility of Detail Radiographic Quality Quality radiographic images represents the, and information is for diagnosis. The of the anatomic structures and the accuracy of their ( ) determine the overall
More informationBiophysical Basis of Optical Radiation Exposure Limits. Bruce E. Stuck
Biophysical Basis of Optical Radiation Exposure Limits Bruce E. Stuck ICNIRP Member bstuck@satx.rr.com ICNIRP 8 th International Radiation Workshop Cape Town International Conference Center Cape Town,
More informationELECTROMAGNETIC SPECTRUM ELECTROMAGNETIC SPECTRUM
LECTURE:2 ELECTROMAGNETIC SPECTRUM ELECTROMAGNETIC SPECTRUM Electromagnetic waves: In an electromagnetic wave the electric and magnetic fields are mutually perpendicular. They are also both perpendicular
More informationChapter 16 Light Waves and Color
Chapter 16 Light Waves and Color Lecture PowerPoint Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. What causes color? What causes reflection? What causes color?
More informationUltrasound & Artifacts
ISSN 2005-7881 Journal of Neurosonology 3(Suppl. 2):1-17, 2011 Ultrasound & Artifacts Siryung Han The Catholic University of Korea Artifacts False image- echoes without anatomic correlate US image dose
More informationUltrasound-modulated optical tomography of absorbing objects buried in dense tissue-simulating turbid media
Ultrasound-modulated optical tomography of absorbing objects buried in dense tissue-simulating turbid media Lihong Wang and Xuemei Zhao Continuous-wave ultrasonic modulation of scattered laser light was
More informationUltrasound Imaging Ultr Michael Dadd 2007
Ultrasound Imaging Ultrasound Physics & Instrumentation - Recommended Reading 1. Diagnostic Ultrasound: Principles and Instruments (7th Ed) Frederick W Kremkau W B Saunders Company 2. Applied Physics &
More informationUltrasonic Linear Array Medical Imaging System
Ultrasonic Linear Array Medical Imaging System R. K. Saha, S. Karmakar, S. Saha, M. Roy, S. Sarkar and S.K. Sen Microelectronics Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata-700064.
More informationExplain what is meant by a photon and state one of its main properties [2]
1 (a) A patient has an X-ray scan taken in hospital. The high-energy X-ray photons interact with the atoms inside the body of the patient. Explain what is meant by a photon and state one of its main properties....
More informationINTRODUCTION. 5. Electromagnetic Waves
INTRODUCTION An electric current produces a magnetic field, and a changing magnetic field produces an electric field Because of such a connection, we refer to the phenomena of electricity and magnetism
More informationMedical Imaging. X-rays, CT/CAT scans, Ultrasound, Magnetic Resonance Imaging
Medical Imaging X-rays, CT/CAT scans, Ultrasound, Magnetic Resonance Imaging From: Physics for the IB Diploma Coursebook 6th Edition by Tsokos, Hoeben and Headlee And Higher Level Physics 2 nd Edition
More informationELECTROMAGNETIC WAVES AND LIGHT. Physics 5 th Six Weeks
ELECTROMAGNETIC WAVES AND LIGHT Physics 5 th Six Weeks What are Electromagnetic Waves Electromagnetic Waves Sound and water waves are examples of waves resulting from energy being transferred from particle
More informationMedical Imaging (EL582/BE620/GA4426)
Medical Imaging (EL582/BE620/GA4426) Jonathan Mamou, PhD Riverside Research Lizzi Center for Biomedical Engineering New York, NY jmamou@riversideresearch.org On behalf of Prof. Daniel Turnbull Outline
More informationX-ray phase-contrast imaging
...early-stage tumors and associated vascularization can be visualized via this imaging scheme Introduction As the selection of high-sensitivity scientific detectors, custom phosphor screens, and advanced
More informationElectromagnetic Waves & the Electromagnetic Spectrum
Electromagnetic Waves & the Electromagnetic Spectrum longest wavelength shortest wavelength The Electromagnetic Spectrum The name given to a group of energy waves that are mostly invisible and can travel
More informationMobile Wireless Communications - Overview
S. R. Zinka srinivasa_zinka@daiict.ac.in October 16, 2014 First of all... Which frequencies we can use for wireless communications? Atmospheric Attenuation of EM Waves 100 % Gamma rays, X-rays and ultraviolet
More informationLongitudinal No, Mechanical wave ~340 m/s (in air) 1,100 feet per second More elastic/denser medium = Greater speed of sound
Type of wave Travel in Vacuum? Speed Speed vs. Medium Light Sound vs. Sound Longitudinal No, Mechanical wave ~340 m/s (in air) 1,100 feet per second More elastic/denser medium = Greater speed of sound
More informationIntroductory Physics, High School Learning Standards for a Full First-Year Course
Introductory Physics, High School Learning Standards for a Full First-Year Course I. C ONTENT S TANDARDS 4.1 Describe the measurable properties of waves (velocity, frequency, wavelength, amplitude, period)
More informationCh.2 Optical Properties of Biological Tissues
Ch.2 Optical Properties of Biological Tissues 2.1 Optical Properties of Biological Tissues 2.1.1 Skin 2.1.2 Eye 2.1.3 Muscle 2.1.4 Fat 2.1.5 Brain 2.1.6 Tumor tissues 2.2 Laser Safety 1 2000/5/17 2.1 Optical
More informationVisual System I Eye and Retina
Visual System I Eye and Retina Reading: BCP Chapter 9 www.webvision.edu The Visual System The visual system is the part of the NS which enables organisms to process visual details, as well as to perform
More informationPhysics 9 Wednesday, February 1, 2012
Physics 9 Wednesday, February 1, 2012 learningcatalytics.com class session ID: 542970 Today: repeat soap bubble; measure λ for laser Today: telescope, human eye Friday: first of 3 days on fluids (liquids,
More informationMedical Imaging: A Look inside. Medical Imaging. Medical Imaging. Visible Human Project
Medical Imaging: A Look inside Medical Imaging Allows physicians to see what had previously been unseeable: internal organs and tissues, bones, a beating heart, etc. Allows physicians to: detect brain
More informationNational 3 Physics Waves and Radiation. 1. Wave Properties
1. Wave Properties What is a wave? Waves are a way of transporting energy from one place to another. They do this through some form of vibration. We see waves all the time, for example, ripples on a pond
More informationAcoustic resolution. photoacoustic Doppler velocimetry. in blood-mimicking fluids. Supplementary Information
Acoustic resolution photoacoustic Doppler velocimetry in blood-mimicking fluids Joanna Brunker 1, *, Paul Beard 1 Supplementary Information 1 Department of Medical Physics and Biomedical Engineering, University
More informationLIGHT AND LIGHTING FUNDAMENTALS. Prepared by Engr. John Paul Timola
LIGHT AND LIGHTING FUNDAMENTALS Prepared by Engr. John Paul Timola LIGHT a form of radiant energy from natural sources and artificial sources. travels in the form of an electromagnetic wave, so it has
More informationChapter 9: Light, Colour and Radiant Energy. Passed a beam of white light through a prism.
Chapter 9: Light, Colour and Radiant Energy Where is the colour in sunlight? In the 17 th century (1600 s), Sir Isaac Newton conducted a famous experiment. Passed a beam of white light through a prism.
More informationChapter 21. Alternating Current Circuits and Electromagnetic Waves
Chapter 21 Alternating Current Circuits and Electromagnetic Waves AC Circuit An AC circuit consists of a combination of circuit elements and an AC generator or source The output of an AC generator is sinusoidal
More information4.6 Waves Waves in air, fluids and solids Transverse and longitudinal waves
4.6 Waves Wave behaviour is common in both natural and man-made systems. Waves carry energy from one place to another and can also carry information. Designing comfortable and safe structures such as bridges,
More informationA miniature all-optical photoacoustic imaging probe
A miniature all-optical photoacoustic imaging probe Edward Z. Zhang * and Paul C. Beard Department of Medical Physics and Bioengineering, University College London, Gower Street, London WC1E 6BT, UK http://www.medphys.ucl.ac.uk/research/mle/index.htm
More informationChapter 5 5.1 What are the factors that determine the thickness of a polystyrene waveguide formed by spinning a solution of dissolved polystyrene onto a substrate? density of polymer concentration of polymer
More information$100 $400 $400 $400 $500
$100 $100 $100 $100 $100 $200 $200 $200 $200 $200 $300 $300 $300 $300 $300 $400 $400 $400 $400 $400 $500 $500 $500 $500 $500 MOVING IN WAVES PURE ENERGY! WHAT S THE FREQUENCY, KENNETH? USE IT OR LOSE IT
More information4. Contrast is the. There must The function of contrast is to:. The types of contrast are.
RADIOGRAPHIC VISIBILITY OF DETAIL STUDY QUESTIONS 1. What is visibility of detail? It is controlled by properties. What are the two factors that affect it? 2. What is sharpness of detail? It is controlled
More informationPractice Problems for Chapter 25-26
Practice Problems for Chapter 25-26 1. What are coherent waves? 2. Describe diffraction grating 3. What are interference fringes? 4. What does monochromatic light mean? 5. What does the Rayleigh Criterion
More informationStandard Grade Physics Health Physics Ink Exercise G1
Standard Grade Physics Health Physics Ink Exercise G1 1. Sounds can travel through : A a vacuum B solids only C liquids only D gases only E solids, liquids and gases 2. A doctor uses a stethoscope like
More informationBetter diagnosis and treatment all-in-one.
Accessories Options duct Specifications hs-on control of the slit lamp without disturbing r view of the retina. solid state diode cavity yellow-red configuration: 5 nm 70 nm green-red configuration: 53
More information3D light microscopy techniques
3D light microscopy techniques The image of a point is a 3D feature In-focus image Out-of-focus image The image of a point is not a point Point Spread Function (PSF) 1D imaging 1 1 2! NA = 0.5! NA 2D imaging
More informationRadar Detection of Lightning. Williams et al. (1989, J. Atmos. Sci.)
Radar Detection of Lightning Williams et al. (1989, J. Atmos. Sci.) Observations of lightning by radar has a history as long as radar itself. Generally accepted that radar echoes from lightning are reflections
More information4.6.1 Waves in air, fluids and solids Transverse and longitudinal waves Properties of waves
4.6 Waves Wave behaviour is common in both natural and man-made systems. Waves carry energy from one place to another and can also carry information. Designing comfortable and safe structures such as bridges,
More informationLight, Lasers, and Holograms Teleclass Webinar!
Welcome to the Supercharged Science Light, Lasers, and Holograms Teleclass Webinar! You can fill out this worksheet as we go along to get the most out of time together, or you can use it as a review exercise
More informationBEAM DISTORTION IN DOPPLER ULTRASOUND FLOW TEST RIGS: MEASUREMENT USING A STRING PHANTOM
BEAM DISTORTION IN DOPPLER ULTRASOUND FLOW TEST RIGS: MEASUREMENT USING A STRING PHANTOM R. Steel, P. J. Fish School of Informatics, University of Wales, Bangor, UK Abstract-The tube in flow rigs used
More informationWave & Electromagnetic Spectrum Notes
Wave & Electromagnetic Spectrum Notes December 17, 2011 I.) Properties of Waves A) Wave: A periodic disturbance in a solid, liquid or gas as energy is transmitted through a medium ( Waves carry energy
More informationTerm Info Picture. A wave that has both electric and magnetic fields. They travel through empty space (a vacuum).
Waves S8P4. Obtain, evaluate, and communicate information to support the claim that electromagnetic (light) waves behave differently than mechanical (sound) waves. A. Ask questions to develop explanations
More informationIntroduction to Ultrasound Physics
Introduction to Ultrasound Physics Vassilis Sboros Medical Physics and Cardiovascular Sciences University of Edinburgh Transverse waves Water remains in position Disturbance traverse producing more wave
More informationEnd Capped High Power Assemblies
Fiberguide s end capped fiber optic assemblies allow the user to achieve higher coupled power into a fiber core by reducing the power density at the air/ silica interface, commonly the point of laser damage.
More informationFill in the blanks. Reading Skill: Compare and Contrast - questions 3, 17
Light and Color Lesson 9 Fill in the blanks Reading Skill: Compare and Contrast - questions 3, 17 How Do You Get Color From White Light? 1 A(n) is a triangular piece of polished glass that refracts white
More informationHuman Retina. Sharp Spot: Fovea Blind Spot: Optic Nerve
I am Watching YOU!! Human Retina Sharp Spot: Fovea Blind Spot: Optic Nerve Human Vision Optical Antennae: Rods & Cones Rods: Intensity Cones: Color Energy of Light 6 10 ev 10 ev 4 1 2eV 40eV KeV MeV Energy
More informationPage 2. Q1.The figure below shows an incomplete electromagnetic spectrum. A microwaves B C ultraviolet D gamma
Q1.The figure below shows an incomplete electromagnetic spectrum. A microwaves B C ultraviolet D gamma (a) What name is given to the group of waves at the position labelled A in the figure above? Tick
More information3. Ultrasound Imaging(2)
3. Ultrasound Imaging(2) Lecture 13, 14 Medical Imaging Systems Jae Gwan Kim, Ph.D. jaekim@gist.ac.kr, X 2220 Department of BioMedical Science and Engineering Gwangju Institute of Sciences and Technology
More informationAnswer: TGC is needed to amplify echoes from deeper structures so that they appear as bright as similar structures located at more shallow depths.
Q47. When performing a sonogram why the sonographer needs to use the TGC? TGC is needed to amplify echoes from deeper structures so that they appear as bright as similar structures located at more shallow
More informationMarr College Physics S3 Physics Waves and Radiation Homework Exercises
Marr College Physics S3 Physics Waves and Radiation Homework Exercises Page 1 Exercise 1 wave characteristics 1. Copy and complete the following: With a _ wave, the particles vibrate at 90 to the direction
More informationInterference [Hecht Ch. 9]
Interference [Hecht Ch. 9] Note: Read Ch. 3 & 7 E&M Waves and Superposition of Waves and Meet with TAs and/or Dr. Lai if necessary. General Consideration 1 2 Amplitude Splitting Interferometers If a lightwave
More informationWaves Q1. MockTime.com. (c) speed of propagation = 5 (d) period π/15 Ans: (c)
Waves Q1. (a) v = 5 cm (b) λ = 18 cm (c) a = 0.04 cm (d) f = 50 Hz Q2. The velocity of sound in any gas depends upon [1988] (a) wavelength of sound only (b) density and elasticity of gas (c) intensity
More informationHoly Cross High School. Medical Physics Homework
Holy Cross High School Medical Physics Homework Homework 1: Refraction 1. A pupil shone light through a rectangular block as shown 75 222 15 40 50 a) The light changes direction as it passes from air to
More information