Lecture 7 Continued Instructor: N R Sivakumar

Size: px
Start display at page:

Download "Lecture 7 Continued Instructor: N R Sivakumar"

Transcription

1 MECH 6491 Engineering Metrology and Measurement Systems Lecture 7 Continued Instructor: N R Sivakumar 1

2 Outline Holography Introduction and Background Theory and types of Holography Holographic Interferometry Theory Applications Speckle Methods Speckle Introduction Speckle intensity and size Speckle Interferometry Theory Applications 2

3 Holography Introduction

4 Holography Introduction Reflection hologram Transmission hologram

5 Holography History Invented in 1948 by Dennis Gabor Leith and Upatnieks (1962) applied laser to holography Holography is the synthesis of interference and diffraction In recording a hologram, two waves interfere to form an interference pattern on the recording medium. When reconstructing the hologram, the reconstructing wave is diffracted by the hologram. 5

6 Holography History When looking at the reconstruction of a 3-D object, it is like looking at the real object By means of holography an original wave field can be reconstructed at a later time at a different location This technique has many applications; we concentrate on holographic interferometry A photograph tells more than a thousand words and a hologram tells more than a thousand photographs 6

7 Holography Advantages Conventional Photography: 2-d version of a 3-d scene Photograph lacks depth perception or parallax Film sensitive only to radiant energy Phase relation (i.e. interference) are lost 7

8 Holography Advantages Holographic Photography: Freezes the intricate wavefront of light that carries all the visual information of the scene To view a hologram, the wavefront is reconstructed View what we would have seen if present at the original scene through the hologram window Provides depth perception and parallax 8

9 Holography Advantages Holographic Photography: Converts phase into amplitude information (in-phase = max amp, out-of-phase = min amp) Interfere wavefront of light from a scene with reference wave The hologram is a complex interference pattern of microscopically spaced fringes holos Greek for whole message 9

10 Holography Recording Laser beam is split in 2 1 wave illuminates the object The object scatters the light onto the hologram plate (object wave) The other wave is reflected directly onto the hologram plate. (reference wave) constitutes a uniform illumination of the hologram plate The hologram plate must be a light-sensitive medium, e.g. a silver halide film plate with high resolution 10

11 Holography Recording Let the object and reference waves in the hologram plane be described by the field amplitudes u o and u. These two waves will interfere resulting in an intensity distribution I u u o 2 u 2 u o 2 u * 0 u u o u * This intensity is allowed to blacken the hologram plate Then it is removed and developed This process is hologram recording 11

12 12 Holography Recording This hologram has a transmittance t proportional to intensity distribution * o * 0 2 o 2 u u u u u I t u Replace the hologram back in the holder in the same position Block object wave and illuminate the hologram with the reference wave (reconstruction wave) U a which will be U multiplied by t o 2 * o 2 a u u u u u u u u u u t

13 Holography Reconstruction The quantity IuI 2 is constant uniform light and the last term thus becomes (apart from a constant) identical to the original object wave u o. We are able to reconstruct the object wave, maintaining its original phase and relative amplitude distribution u o by looking through the hologram, object can be seen in 3D even though the physical object has been removed Therefore this reconstructed wave is also called the virtual wave 13

14 Hologram Reconstruction u a u u 2 u u o 2 u 2 u * 0 u Direct wave: corresponds to zeroth order grating diffraction pattern Object wave: gives virtual image of the object (reconstructs object wavefront) first order diffraction Conjugate wave: conjugate point, real image (not useful since image is inside-out) negative first order diffraction In general, we wish to view only the object wave the other waves just confuse the issue 2 u o 14

15 Hologram Reconstruction Reference wave Object wave Real image Virtual image Conjugate wave Direct wave -z z z=0 15

16 Hologram Reconstruction Use an off-axis system to record the hologram, ensuring separation of the three waves on reconstruction Reference wave Object wave Direct wave Virtual image Conjugate wave Real image 16

17 Holography Reconstruction Alternative method of recording Fewer components hence more stable Can you spot the difference.. 17

18 Hologram Reflection vs. Transmission Transmission hologram: reference and object waves traverse the film from the same side Reflection hologram: reference and object waves traverse the emulsion from opposite sides View in Transmission View in reflection 18

19 Hologram - Transmission 19

20 Hologram - Reflection 20

21 Hologram: Wavelength With a different color, the virtual image will appear at a different angle (i.e. as a grating, the hologram disperses light of different wavelengths at different angles) Volume hologram: emulsion thickness >> fringe spacing Can be used to reproduce images in their original color when illuminated by white light. Use multiple exposures of scene in three primary colors (R,G,B) 21

22 Volume Hologram Reconstruction wave must be a duplication of the reference wave Reflection hologram can be reconstructed in white light giving images in their original color 22

23 Hologram - Applications Microscopy M = r/ s Increase magnification by viewing hologram with longer wavelength Produce hologram with x-ray laser, when viewed with visible light M ~ d images of microscopic objects DNA, viruses 23

24 Hologram - Applications Interferometry Small changes in OPL can be measured by viewing the direct image of the object and the holographic image (interference pattern produce finges Δl) E.g. stress points, wings of fruit fly in motion, compression waves around a speeding bullet, convection currents around a hot filament 24

25 Holographic Interferometry Two waves reflected from two identical objects could interfere With the method of holography now at hand, we are able to realize this by storing the wavefront scattered from an object in a hologram. We then can recreate this wavefront by hologram reconstruction, where and when we choose. 25

26 Holographic Interferometry For instance, we can let it interfere with the wave scattered from the object in a deformed state. This technique belongs to the field of holographic interferometry In the case of static deformations, the methods can be grouped into two procedures, double-exposure and real-time interferometry. (Vest 1979; Erf 1974; Jones and Wykes 1989). 26

27 Double Exposure Interferometry Two holograms of the object recorded in same medium at different time instants If conditions at the recordings different interference between the reconstructed holographic images reveals deformations simple to carry out avoids the problem of realignment distortion minimized compares only two time instances 27

28 Real Time Interferometry The observer sees any deformation of the object (in scale of λ) in real time as interference between the real object and the holographic image of the object at rest Disadvantage is that the hologram must be replaced in its original position with very high accuracy 28

29 Holographic Interferograms Deflection of a rectangular plate fastened with five struts and subjected to a uniform pressure A bullet in flight observed through a doubly-exposed hologram Detection of debonded region of a honeycomb construction panel 29

30 Holographic Vibration Analysis Make hologram of vibrating object Maximum vibration amplitude should be limited to tens of wavelengths Illumination of hologram yields image on which is superimposed interference fringes Fringes are contour lines of equal vibration amplitude 30

31 Speckle Introduction When looking at the laser light scattered from a rough surface, one sees a granular pattern This so-called speckle pattern can be regarded as a multiple wave interference with random phases Speckle is considered a mere nuisance But from the beginning of 1970 there were several reports from experiments in which speckle was exploited as a measuring tool. 31

32 Speckle Introduction light is scattered from a rough surface of height variations greater than the. In white light illumination, this effect is scarcely observable??? Applying laser light, however, gives the scattered light a characteristic granular appearance 32

33 Speckle Introduction The probability density function P, for the intensity in a speckle pattern is given as Where I is the mean intensity. The intensity of a speckle pattern thus obeys negative exponential statistics From this plot we see that the most probable intensity value is zero, that is, black. 33

34 Speckle Size Objective speckle size (without lens) is given by Subjective speckle size (with Objective speckle size lens) is given by Subjective speckle size 34

35 Speckle Interferometry Laser speckle methods can be utilized in many ways; Speckleshearing enables direct measurements of displacement derivatives related to strains The principle of speckleshearing (shearography) is to bring the rays scattered from one point of the object into interference with rays from neighboring point (Hung and Taylor 1973; Leendertz and Butters 1973). 35

36 Speckle Interferometry This can be obtained in a speckle-shearing interferometric camera where one half of the camera lens is covered by a thin glass wedge In that way, the two images focused by each half of the lens are laterally sheared If the wedge is oriented to shear in the x, the rays from a point P(x, y) on the object will interfere in the image plane with those from a neighbouring point P(x+ x, y) The shearing x is proportional to the wedge angle When the object is deformed there is a relative displacement between the two points that produces a relative optical phase change 36

37 Speckle Interferometry For small shear angles x the equation can be approximated to (k= 2 / ) For out of plane measurement normal angle ( =0) is enough and the equation becomes For both in plane and out of plane measurement that is both u and w, we need to use different angle 37

38 Electronic Speckle Interferometry 38

39 Electronic Speckle Interferometry (a) Out-of-plane displacement fringes (w) and slope fringes ( w/ x) for a aluminium plate loaded at the centre. x is 6 mm, and w = 2.5 µm and (b) Out-of-plane displacement fringe pattern (w) and slope pattern ( w/ y) for the same object. The shear y is 7 mm. 39

40 Speckle and Holography Electronic shearography (ES) used for non-destructive testing of a ceramic material. (a) A vertical crack is clearly visualized by ES as a fringe in the centre of the sample and (b) The crack is not detected using TV holography 40

41 ESPI for NDT To develop a non-destructive In-line subsurface defects detection system GOOD part BAD part Digital Shearography Setup Able to detect surface/subsurface defects effectively and efficiently 41

42 ESPI for NDT Application Unpolished Silicon Wafers Unpolished Silicon Wafers Polishing (whole batch) Silicon wafers no Defect? yes yes Defect? no Polishing (good wafers only) READY FOR IC FABRICATION PROCESS RECYCLE BIN Conventional process Patterned Wafer Estimated cost savings more than S$1million/year for ISP New process RECYCLE BIN 42

43 MECH 6491 Engineering Metrology and Measurement Systems Lecture 8 Instructor: N R Sivakumar 43

44 Outline Light Sources Incoherent Light Sources Coherent Light Sources Detectors PhotoElectric Detectors CCD Camera 44

45 Spontaneous Emission Most light sources are incoherent (candle light to Sun) They all radiate light due to spontaneous emission Here we will consider some sources often used in scientific applications These are incandescent sources, low-pressure gas discharge lamps and high-pressure gas discharge-arc lamps They are commonly rated according to their electric power consumption 45

46 Spontaneous Emission Energy-level diagram for a molecule is shown The atom by some process is raised to an excited state E 3 Then it drops to E 2, E 1 and E 0 in successive steps E2 E1 h hc / Energy difference between E 2 and E 1 is released as electromagnetic radiation of frequency given by where h = x Js is the Planck constant This might be the situation in an ordinary light source where the transition occurs spontaneously hence called spontaneous emission 46

47 Incoherent Light Sources Tungsten halogen lamps - common incandescent source Quartz tungsten halogen lamps (QTH) produce a bright, stable, visible and infrared output and is the most It emits radiation due to the thermal excitation of source atoms or molecules Tungsten evaporates the filament and deposits inside the bulb This blackens the bulb wall and thins the tungsten filament, gradually reducing the light output halogen gas removes the deposited tungsten, and returns it to the hot filament, leaving the inside of the envelope clean, and greatly increases lamp life. This process is called the halogen cycle 47

48 Incoherent Light Sources Low Pressure Gas Discharge lamps - Electric current passes through a gas Gas atoms or molecules become ionized to conduct the current At low current density and pressures, electrons bound to the gas atoms become excited to well-defined higher-energy levels Radiation is emitted as the electron falls to a lower energy level characteristic of the particular type of gas. The spectral distribution is then a number of narrow fixed spectral lines with little background radiation 48

49 Incoherent Light Sources Low Pressure Gas Discharge lamps - brightest conventional sources of optical radiation High-current-density arc discharges through high-pressure gas Thermal conditions in the arc are such that gas atoms are highly excited resulting in a volume of plasma The hot plasma emits like an incandescent source, while ionized atoms emit substantially broadened lines The most common sources of this type are the Xenon (Xe) and mercury (Hg) short arc lamps 49

50 Spontaneous Emission Excited atoms normally emit light spontaneously Photons are uncorrelated and independent Incoherent light 50

51 Stimulated Emission Excited atoms can be stimulated into duplicating passing light Photons are correlated and identical Coherent light 51

52 Coherent Light Sources Spontaneous Emission Stimulated Emission Stimulated Absorption Population Inversion Optical Pumping As postulated by Einstein, also another type of transition is possible E2 E1 h hc / If a photon of frequency given by Equation passes the atom it might trigger the transition from E2 to E1 thereby releasing a new photon of the same frequency by so-called stimulated emission 52

53 Coherent Light Sources Under normal conditions, the number of atoms in a state tends to decrease as its energy increases This means that there will be a larger population in the lower state of a transition than in the higher state Therefore photons passing the atom are far more likely to be absorbed than to stimulate emission 53

54 Coherent Light Sources Under these conditions, spontaneous emission dominates However, if the excitation of the atoms is sufficiently strong, the population of the upper level might become higher than that of the lower level This is called population inversion Then by passing of a photon of frequency given by equation it will be more likely to stimulate emission from the excited state than to be absorbed by the lower state 54

55 Coherent Light Sources This is the condition that must be obtained in a laser This results is laser gain or amplification, a net increase in the number of photons with the transition energy They produce narrow beams of intense light They often have pure colors They are dangerous to eyes Reflected laser light has a funny speckled look 55

56 LASER LOSER - Light Oscillation by STIMULATED Emission of Radiation LASER - Light Amplification by STIMULATED Emission of Radiation 56

57 Laser Amplification Stimulated emission can amplify light Laser medium contains excited atom-like systems Photons must have appropriate wavelength, polarization, and orientation to be duplicated Duplication is perfect; photons are clones 57

58 Laser Oscillation Laser medium in a resonator produces oscillator A spontaneous photon is duplicated over and over Duplicated photons leak from semitransparent mirror Photons from oscillator are identical 58

59 Laser Oscillation 59

60 Properties of Laser Light Coherence identical photons Monochromaticity; Controllable wavelength/frequency nice colors Beam divergence; Controllable spatial structure narrow beams Brightness Energy storage and retrieval intense pulses Giant interference effects Apart from these issues, laser light is just light 60

61 Monochromaticity I λ 1 λ 0 λ 2 Wavelength Spectral Width = λ 2 - λ 1 61

62 Coherence c L c c 1 62

63 Laser Modes Although the laser light has a well-defined wavelength (or frequency), it has nevertheless a certain frequency spread. By spectral analysis of the light, it turns out that it consists of one or more distinct frequencies called resonator modes, separated by a frequency where c = the speed of light and L is the distance between the laser mirrors, i.e. the resonator length 63

64 Beam Divergence FLASH LAMP = 25 0 LASER = BRIGHTNESS POWER UNIT AREA/ UNIT SOLID ANGLE 64

65 CW and Pulsed Lasers E E Pulse duration Peak Power Average power Continuous Wave t Pulsed Laser t 65

66 Types of Lasers Gas (HeNe, CO2, Argon, Krypton) Powered by electricity Solid state (Ruby, Nd:YAG, Ti:Sapphire, Diode) Powered by electricity or light Liquid (Dye, Jello) Powered by light Chemical (HF) 66

67 Coherent Light Sources Inside a discharge tube is a gas mixture of helium and neon. 5 to 12 times more helium than neon. By applying voltage to the electrodes, the resulting electric field will accelerate free electrons These collide with helium atoms raising them to a higher energy level. By collision between helium and neon atoms, the latter are raised to a higher energy level This constitute the pumping process. The neon atoms, which constitute the active medium, return to a lower energy level and the energy difference is released as electromagnetic radiation 67

68 He Ne Laser 68

69 Detectors Chemical detectors photographic film, photopolymers They do not give a signal output in the usual sense Electronic detectors thermal detectors photon detectors 69

70 Detectors In thermal detectors, the absorption of light raises the temperature of the device This in turn results in changes in some temperaturedependent parameter (e.g. electrical conductivity) Most thermal detectors are rather inefficient and quite slow (hence, not useful in optical metrology) Fire detection and alarms 70

71 Detectors Photon detectors work on the photoeffect Absorption of photons by some materials results directly in an electronic transition to a higher energy level Since the energy of a single photon is E = h = hc/, photon detectors have a maximum for operation For detectors operating in the infrared, photon energy thermal energy of the atoms in the detector Detectors operating above a of 3 µm must be cooled below 77K 71

72 Detectors The photoeffect takes two forms: external and internal The former process involves photoelectric emission, in which the photo-generated electrons escape from the material (the photocathode) as free electrons with a maximum kinetic energy given by Einstein's photoelectric equation where the work function W is the energy difference between the vacuum and the Fermi levels of the material 72

73 Detectors Photoemissive devices usually take the form of vacuum tubes called phototubes Electrons emitted from the photocathode travel to an electrode (the anode) which is kept at a higher electric potential As a result, an electric current proportional to the photon flux incident on the cathode is created in the circuit In a photomultiplier, the electrons are accelerated towards a series of electrodes maintained at successively higher potentials 73

74 Detectors From the electrodes a cascade of electrons are emitted by secondary emission, resulting in an amplification A microchannel plate consists of an array of channels (ID ~ 10 µm) in a slab of insulating material (0.5 mm thick) Each channel acts like a miniature photomultiplier tube Emerging from the channels, the electrons can generate light (optical image) by striking a phosphor screen. In the internal photo-effect, the photo-excited carriers (electrons and holes) remain within the material 74

75 Detectors Photoconductors rely on the light-induced increase in the conductivity - almost all semiconductors The absorption of photon results in the generation of a free electron, and a hole is generated An external voltage applied causes the electrons and holes to move, resulting in a detectable electric current The detector operates by registering the current proportional to the photon flux 75

76 Detectors Photodiode is a p-n junction structure where photons absorbed generate electrons and holes which are subject to electric field within that layer The two carriers drift in opposite directions and an electric current is induced in the external circuit Here the circuit current is directly proportional to the incident light irradiance 76

77 CCD Cameras CCDs are a series of Metal oxide semicon (MOS) capacitors A semiconductor substrate is covered with a thin layer of insulating silicon oxide - insulates the Si from electrode. When a positive voltage is applied between the electrode and the Si, holes in p-type Si will be repelled, creating a region free of mobile carriers directly underneath the electrode 77

78 CCD Cameras This region is known as depletion region and has a thickness of few microns The electrodes are transparent for >400 nm If incident photon has an energy larger than the bandgap in Si, a charge packet is formed consisting of photon-electrons which were created in the vicinity of a specific electrode 78

79 CCD Cameras At the heart of every digital camera is a Charge Coupled Device (CCD) typically about a square centimeter in size. 79

80 CCD Cameras The CCD is comprised of many individual signal capture units, each of which corresponds to a single pixel in the final digital image. 80

81 CCD Cameras Light - incoming photons falls onto the CCD chip surface This generates free electrons in the silicon of the CCD in proportion to the number of photons striking it These electrons collect in little packets created by the silicon geometry and surrounding electrical circuitry laid out in a 2D grid on the chip Typical CCD chips have from 1 to 5 million charge packets 81

82 CCD Cameras At the heart of the CCD is these metal oxide semiconductors (MOS) which allow the charge of electrons to build up in wells in the silicon base. 82

83 CCD Cameras The CCD operates on the principle of charge coupling. The packets of charged electrons can be moved one row at a time by varying the voltage of adjacent rows thereby creating a potential well which couples two rows and causes the charge to move over 83

84 CCD Cameras Buckets on conveyor belts depict how each bucket contains a different amount of light (shown as rainwater) and how these buckets are shifted in an orderly fashion 84

85 CCD Cameras In this way the quantity of water (or electrons representing light) in each bucket (or packet) are counted. In a typical CCD this happens very fast: about 30 times per second for every one of the million or so "buckets" on the CCD. 85

86 To increase the efficiency of reading the output of the CCD array there are several different designs. One type transfers the entire frame into an empty storage array, while others alternate empty rows with collecting rows. 86

87 CCDs can be used to collect an image in one of three ways, either one pixel at a time, one row at a time, or as an entire area at once. 87

LASER. Light Amplification by Stimulated Emission of Radiation

LASER. Light Amplification by Stimulated Emission of Radiation LASER Light Amplification by Stimulated Emission of Radiation Laser Fundamentals The light emitted from a laser is monochromatic, that is, it is of one color/wavelength. In contrast, ordinary white light

More information

Unit-2 LASER. Syllabus: Properties of lasers, types of lasers, derivation of Einstein A & B Coefficients, Working He-Ne and Ruby lasers.

Unit-2 LASER. Syllabus: Properties of lasers, types of lasers, derivation of Einstein A & B Coefficients, Working He-Ne and Ruby lasers. Unit-2 LASER Syllabus: Properties of lasers, types of lasers, derivation of Einstein A & B Coefficients, Working He-Ne and Ruby lasers. Page 1 LASER: The word LASER is acronym for light amplification by

More information

-I (PH 6151) UNIT-V PHOTONICS AND FIBRE OPTICS

-I (PH 6151) UNIT-V PHOTONICS AND FIBRE OPTICS Engineering Physics -I (PH 6151) UNIT-V PHOTONICS AND FIBRE OPTICS Syllabus: Lasers Spontaneous and stimulated emission Population Inversion -Einstein s co-efficient (Derivation)- types of lasers-nd-yag,co

More information

Because light behaves like a wave, we can describe it in one of two ways by its wavelength or by its frequency.

Because light behaves like a wave, we can describe it in one of two ways by its wavelength or by its frequency. Light We can use different terms to describe light: Color Wavelength Frequency Light is composed of electromagnetic waves that travel through some medium. The properties of the medium determine how light

More information

OPAC 101 Introduction to Optics

OPAC 101 Introduction to Optics OPAC 101 Introduction to Optics Topic 2 Light Sources Department of http://www1.gantep.edu.tr/~bingul/opac101 Optical & Acustical Engineering Gaziantep University Sep 2017 Sayfa 1 Light Sources: maybe

More information

B.Tech. First Semester Examination Physics-1 (PHY-101F)

B.Tech. First Semester Examination Physics-1 (PHY-101F) B.Tech. First Semester Examination Physics-1 (PHY-101F) Note : Attempt FIVE questions in all taking least two questions from each Part. All questions carry equal marks Part-A Q. 1. (a) What are Newton's

More information

Unit I LASER Engineering Physics

Unit I LASER Engineering Physics Introduction LASER stands for light Amplification by Stimulated Emission of Radiation. The theoretical basis for the development of laser was provided by Albert Einstein in 1917. In 1960, the first laser

More information

Light Emission. Today s Topics. Excitation/De-Excitation 10/26/2008. Excitation Emission Spectra Incandescence

Light Emission. Today s Topics. Excitation/De-Excitation 10/26/2008. Excitation Emission Spectra Incandescence Light Emission Excitation Emission Spectra Incandescence Absorption Spectra Today s Topics Excitation/De-Excitation Electron raised to higher energy level Electron emits photon when it drops back down

More information

Lasers & Holography. Ulrich Heintz Brown University. 4/5/2016 Ulrich Heintz - PHYS 1560 Lecture 10 1

Lasers & Holography. Ulrich Heintz Brown University. 4/5/2016 Ulrich Heintz - PHYS 1560 Lecture 10 1 Lasers & Holography Ulrich Heintz Brown University 4/5/2016 Ulrich Heintz - PHYS 1560 Lecture 10 1 Lecture schedule Date Topic Thu, Jan 28 Introductory meeting Tue, Feb 2 Safety training Thu, Feb 4 Lab

More information

Lasers and Electro-optics

Lasers and Electro-optics Lasers and Electro-optics Second Edition CHRISTOPHER C. DAVIS University of Maryland III ^0 CAMBRIDGE UNIVERSITY PRESS Preface to the Second Edition page xv 1 Electromagnetic waves, light, and lasers 1

More information

Experiment 3 1. The Michelson Interferometer and the He- Ne Laser Physics 2150 Experiment No. 3 University of Colorado

Experiment 3 1. The Michelson Interferometer and the He- Ne Laser Physics 2150 Experiment No. 3 University of Colorado Experiment 3 1 Introduction The Michelson Interferometer and the He- Ne Laser Physics 2150 Experiment No. 3 University of Colorado The Michelson interferometer is one example of an optical interferometer.

More information

Modern optics Lasers

Modern optics Lasers Chapter 13 Phys 322 Lecture 36 Modern optics Lasers Reminder: Please complete the online course evaluation Last lecture: Review discussion (no quiz) LASER = Light Amplification by Stimulated Emission of

More information

Single Photon detectors

Single Photon detectors Single Photon detectors Outline Motivation for single photon detection Semiconductor; general knowledge and important background Photon detectors: internal and external photoeffect Properties of semiconductor

More information

LASERS. Dr D. Arun Kumar Assistant Professor Department of Physical Sciences Bannari Amman Institute of Technology Sathyamangalam

LASERS. Dr D. Arun Kumar Assistant Professor Department of Physical Sciences Bannari Amman Institute of Technology Sathyamangalam LASERS Dr D. Arun Kumar Assistant Professor Department of Physical Sciences Bannari Amman Institute of Technology Sathyamangalam General Objective To understand the principle, characteristics and types

More information

Laserphysik. Prof. Yong Lei & Dr. Yang Xu. Fachgebiet Angewandte Nanophysik, Institut für Physik

Laserphysik. Prof. Yong Lei & Dr. Yang Xu. Fachgebiet Angewandte Nanophysik, Institut für Physik Laserphysik Prof. Yong Lei & Dr. Yang Xu Fachgebiet Angewandte Nanophysik, Institut für Physik Contact: yong.lei@tu-ilmenau.de; yang.xu@tu-ilmenau.de Office: Heisenbergbau V 202, Unterpörlitzer Straße

More information

What can laser light do for (or to) me?

What can laser light do for (or to) me? What can laser light do for (or to) me? Phys 1020, Day 15: Questions? Refection, refraction LASERS: 14.3 Next Up: Finish lasers Cameras and optics 1 Eyes to web: Final Project Info Light travels more slowly

More information

Name the region of the electromagnetic radiation emitted by the laser. ...

Name the region of the electromagnetic radiation emitted by the laser. ... 1. An argon-laser emits electromagnetic radiation of wavelength 5.1 10 7 m. The radiation is directed onto the surface of a caesium plate. The work function energy for caesium is 1.9 ev. (i) Name the region

More information

Materialwissenschaft und Nanotechnologie. Introduction to Lasers

Materialwissenschaft und Nanotechnologie. Introduction to Lasers Materialwissenschaft und Nanotechnologie Introduction to Lasers Dr. Andrés Lasagni Lehrstuhl für Funktionswerkstoffe Sommersemester 007 1-Introduction to LASER Contents: Light sources LASER definition

More information

Photon Instrumentation. First Mexican Particle Accelerator School Guanajuato Oct 6, 2011

Photon Instrumentation. First Mexican Particle Accelerator School Guanajuato Oct 6, 2011 Photon Instrumentation First Mexican Particle Accelerator School Guanajuato Oct 6, 2011 Outline The Electromagnetic Spectrum Photon Detection Interaction of Photons with Matter Photoelectric Effect Compton

More information

Chapter 24 Photonics Question 1 Question 2 Question 3 Question 4 Question 5

Chapter 24 Photonics Question 1 Question 2 Question 3 Question 4 Question 5 Chapter 24 Photonics Data throughout this chapter: e = 1.6 10 19 C; h = 6.63 10 34 Js (or 4.14 10 15 ev s); m e = 9.1 10 31 kg; c = 3.0 10 8 m s 1 Question 1 Visible light has a range of photons with wavelengths

More information

Chemistry Instrumental Analysis Lecture 19 Chapter 12. Chem 4631

Chemistry Instrumental Analysis Lecture 19 Chapter 12. Chem 4631 Chemistry 4631 Instrumental Analysis Lecture 19 Chapter 12 There are three major techniques used for elemental analysis: Optical spectrometry Mass spectrometry X-ray spectrometry X-ray Techniques include:

More information

Sunlight. 1 radiation.

Sunlight. 1 radiation. Sunlight The eye has evolved to see a narrow range of EM waves which we call 'visible light'. This visible range of frequency is due to the light comes from the Sun. The photosphere of the Sun is a blackbody

More information

25 Instruments for Optical Spectrometry

25 Instruments for Optical Spectrometry 25 Instruments for Optical Spectrometry 25A INSTRUMENT COMPONENTS (1) source of radiant energy (2) wavelength selector (3) sample container (4) detector (5) signal processor and readout (a) (b) (c) Fig.

More information

Stepwise Solution Important Instructions to examiners:

Stepwise Solution Important Instructions to examiners: (ISO/IEC - 700-005 Certified) SUMMER 05 EXAMINATION Subject Code: 70 Model Answer (Applied Science- Physics) Page No: 0/6 Que. No. Sub. Que. Important Instructions to examiners: ) The answers should be

More information

AS 101: Day Lab #2 Summer Spectroscopy

AS 101: Day Lab #2 Summer Spectroscopy Spectroscopy Goals To see light dispersed into its constituent colors To study how temperature, light intensity, and light color are related To see spectral lines from different elements in emission and

More information

Analytical Spectroscopy Review

Analytical Spectroscopy Review Analytical Spectroscopy Review λ = wavelength ν = frequency V = velocity = ν x λ = 2.998 x 10 8 m/sec = c (in a vacuum) ν is determined by source and does not change as wave propogates, but V can change

More information

DIFFRACTION GRATING. OBJECTIVE: To use the diffraction grating in the formation of spectra and in the measurement of wavelengths.

DIFFRACTION GRATING. OBJECTIVE: To use the diffraction grating in the formation of spectra and in the measurement of wavelengths. DIFFRACTION GRATING OBJECTIVE: To use the diffraction grating in the formation of spectra and in the measurement of wavelengths. THEORY: The operation of the grating is depicted in Fig. 1 on page Lens

More information

Reference literature. (See: CHEM 2470 notes, Module 8 Textbook 6th ed., Chapters )

Reference literature. (See: CHEM 2470 notes, Module 8 Textbook 6th ed., Chapters ) September 17, 2018 Reference literature (See: CHEM 2470 notes, Module 8 Textbook 6th ed., Chapters 13-14 ) Reference.: https://slideplayer.com/slide/8354408/ Spectroscopy Usual Wavelength Type of Quantum

More information

LASER. Challenging MCQ questions by The Physics Cafe. Compiled and selected by The Physics Cafe

LASER. Challenging MCQ questions by The Physics Cafe. Compiled and selected by The Physics Cafe LSER hallenging MQ questions by The Physics afe ompiled and selected by The Physics afe www.thephysicsafe.com www.pmc.sg 1 laser point creates a spot on a screen as it reflects 70% of the light striking

More information

Name :. Roll No. :... Invigilator s Signature :.. CS/B. Tech (New)/SEM-1/PH-101/ PHYSICS-I

Name :. Roll No. :... Invigilator s Signature :.. CS/B. Tech (New)/SEM-1/PH-101/ PHYSICS-I Name :. Roll No. :..... Invigilator s Signature :.. CS/B. Tech (New)/SEM-1/PH-101/2011-12 2011 PHYSICS-I Time Allotted : 3 Hours Full Marks : 70 The figures in the margin indicate full marks. Candidates

More information

Astronomy. Optics and Telescopes

Astronomy. Optics and Telescopes Astronomy A. Dayle Hancock adhancock@wm.edu Small 239 Office hours: MTWR 10-11am Optics and Telescopes - Refraction, lenses and refracting telescopes - Mirrors and reflecting telescopes - Diffraction limit,

More information

Optical Systems Program of Studies Version 1.0 April 2012

Optical Systems Program of Studies Version 1.0 April 2012 Optical Systems Program of Studies Version 1.0 April 2012 Standard1 Essential Understand Optical experimental methodology, data analysis, interpretation, and presentation strategies Essential Understandings:

More information

Lecture 0. NC State University

Lecture 0. NC State University Chemistry 736 Lecture 0 Overview NC State University Overview of Spectroscopy Electronic states and energies Transitions between states Absorption and emission Electronic spectroscopy Instrumentation Concepts

More information

Photoelectric effect

Photoelectric effect Laboratory#3 Phys4480/5480 Dr. Cristian Bahrim Photoelectric effect In 1900, Planck postulated that light is emitted and absorbed in discrete but tiny bundles of energy, E = hν, called today photons. Here

More information

Quantum Mechanics (made fun and easy)

Quantum Mechanics (made fun and easy) Lecture 7 Quantum Mechanics (made fun and easy) Why the world needs quantum mechanics Why the world needs quantum mechanics Why the world needs quantum mechanics Why the world needs quantum mechanics Why

More information

Interested in exploring science or math teaching as a career?

Interested in exploring science or math teaching as a career? Interested in exploring science or math teaching as a career? Start with Step 1: EDUC 2020 (1 credit) Real experience teaching real kids! No commitment to continue with education courses Registration priority

More information

Chemistry 311: Instrumentation Analysis Topic 2: Atomic Spectroscopy. Chemistry 311: Instrumentation Analysis Topic 2: Atomic Spectroscopy

Chemistry 311: Instrumentation Analysis Topic 2: Atomic Spectroscopy. Chemistry 311: Instrumentation Analysis Topic 2: Atomic Spectroscopy Topic 1: Atomic Spectroscopy Text: Chapter 12,13 & 14 Rouessac (~2 weeks) 1.0 Review basic concepts in Spectroscopy 2.0 Atomic Absorption and Graphite Furnace Instruments 3.0 Inductively Coupled Plasmas

More information

Energetic particles and their detection in situ (particle detectors) Part II. George Gloeckler

Energetic particles and their detection in situ (particle detectors) Part II. George Gloeckler Energetic particles and their detection in situ (particle detectors) Part II George Gloeckler University of Michigan, Ann Arbor, MI University of Maryland, College Park, MD Simple particle detectors Gas-filled

More information

Revision Guide. Chapter 7 Quantum Behaviour

Revision Guide. Chapter 7 Quantum Behaviour Revision Guide Chapter 7 Quantum Behaviour Contents CONTENTS... 2 REVISION CHECKLIST... 3 REVISION NOTES... 4 QUANTUM BEHAVIOUR... 4 Random arrival of photons... 4 Photoelectric effect... 5 PHASE AN PHASORS...

More information

Radionuclide Imaging MII Detection of Nuclear Emission

Radionuclide Imaging MII Detection of Nuclear Emission Radionuclide Imaging MII 3073 Detection of Nuclear Emission Nuclear radiation detectors Detectors that are commonly used in nuclear medicine: 1. Gas-filled detectors 2. Scintillation detectors 3. Semiconductor

More information

Chapter 4 Scintillation Detectors

Chapter 4 Scintillation Detectors Med Phys 4RA3, 4RB3/6R03 Radioisotopes and Radiation Methodology 4-1 4.1. Basic principle of the scintillator Chapter 4 Scintillation Detectors Scintillator Light sensor Ionizing radiation Light (visible,

More information

Introduction CHAPTER 01. Light and opto-semiconductors. Opto-semiconductor lineup. Manufacturing process of opto-semiconductors.

Introduction CHAPTER 01. Light and opto-semiconductors. Opto-semiconductor lineup. Manufacturing process of opto-semiconductors. CHAPTER 0 Light and opto-semiconductors - -2 Light Opto-semiconductors P. 0 P. 3 2 Opto-semiconductor lineup P. 5 3 Manufacturing process of opto-semiconductors P. 6 9 CHAPTER 0. Light and opto-semiconductors

More information

Practice Paper-3. Q. 2. An electron beam projected along + X-axis, in a magnetic field along the + Z-axis. What is

Practice Paper-3. Q. 2. An electron beam projected along + X-axis, in a magnetic field along the + Z-axis. What is Practice Paper-3 Q. 1. An electric dipole of dipole moment 20 10 6 cm is enclosed by a closed surface. What is the net flux coming out of the surface? Q. 2. An electron beam projected along + X-axis, in

More information

10/2/2008. hc λ. νλ =c. proportional to frequency. Energy is inversely proportional to wavelength And is directly proportional to wavenumber

10/2/2008. hc λ. νλ =c. proportional to frequency. Energy is inversely proportional to wavelength And is directly proportional to wavenumber CH217 Fundamentals of Analytical Chemistry Module Leader: Dr. Alison Willows Electromagnetic spectrum Properties of electromagnetic radiation Many properties of electromagnetic radiation can be described

More information

2. Discrete means unique, that other states don t overlap it. 3. Electrons in the outer electron shells have greater potential energy.

2. Discrete means unique, that other states don t overlap it. 3. Electrons in the outer electron shells have greater potential energy. 30 Light Emission Answers and Solutions for Chapter 30 Reading Check Questions 1. At these high frequencies, ultraviolet light is emitted. 2. Discrete means unique, that other states don t overlap it.

More information

Chemistry Instrumental Analysis Lecture 5. Chem 4631

Chemistry Instrumental Analysis Lecture 5. Chem 4631 Chemistry 4631 Instrumental Analysis Lecture 5 Light Amplification by Stimulated Emission of Radiation High Intensities Narrow Bandwidths Coherent Outputs Applications CD/DVD Readers Fiber Optics Spectroscopy

More information

What do we study and do?

What do we study and do? What do we study and do? Light comes from electrons transitioning from higher energy to lower energy levels. Wave-particle nature of light Wave nature: refraction, diffraction, interference (labs) Particle

More information

Chemistry 311: Instrumentation Analysis Topic 2: Atomic Spectroscopy. Chemistry 311: Instrumentation Analysis Topic 2: Atomic Spectroscopy

Chemistry 311: Instrumentation Analysis Topic 2: Atomic Spectroscopy. Chemistry 311: Instrumentation Analysis Topic 2: Atomic Spectroscopy Topic 2b: X-ray Fluorescence Spectrometry Text: Chapter 12 Rouessac (1 week) 4.0 X-ray Fluorescence Download, read and understand EPA method 6010C ICP-OES Winter 2009 Page 1 Atomic X-ray Spectrometry Fundamental

More information

RED. BLUE Light. Light-Matter

RED. BLUE Light.   Light-Matter 1 Light-Matter This experiment demonstrated that light behaves as a wave. Essentially Thomas Young passed a light of a single frequency ( colour) through a pair of closely spaced narrow slits and on the

More information

PHYSICS nd TERM Outline Notes (continued)

PHYSICS nd TERM Outline Notes (continued) PHYSICS 2800 2 nd TERM Outline Notes (continued) Section 6. Optical Properties (see also textbook, chapter 15) This section will be concerned with how electromagnetic radiation (visible light, in particular)

More information

Laser Physics OXFORD UNIVERSITY PRESS SIMON HOOKER COLIN WEBB. and. Department of Physics, University of Oxford

Laser Physics OXFORD UNIVERSITY PRESS SIMON HOOKER COLIN WEBB. and. Department of Physics, University of Oxford Laser Physics SIMON HOOKER and COLIN WEBB Department of Physics, University of Oxford OXFORD UNIVERSITY PRESS Contents 1 Introduction 1.1 The laser 1.2 Electromagnetic radiation in a closed cavity 1.2.1

More information

Lasers E 6 E 4 E 3 E 2 E 1

Lasers E 6 E 4 E 3 E 2 E 1 Lasers Laser is an acronym for light amplification by stimulated emission of radiation. Here the process of stimulated emission is used to amplify light radiation. Spontaneous emission: When energy is

More information

Practical 1P4 Energy Levels and Band Gaps

Practical 1P4 Energy Levels and Band Gaps Practical 1P4 Energy Levels and Band Gaps What you should learn from this practical Science This practical illustrates some of the points from the lecture course on Elementary Quantum Mechanics and Bonding

More information

Spectroscopy: Introduction. Required reading Chapter 18 (pages ) Chapter 20 (pages )

Spectroscopy: Introduction. Required reading Chapter 18 (pages ) Chapter 20 (pages ) Spectroscopy: Introduction Required reading Chapter 18 (pages 378-397) Chapter 20 (pages 424-449) Spectrophotometry is any procedure that uses light to measure chemical concentrations Properties of Light

More information

Higher Physics. Particles and Waves

Higher Physics. Particles and Waves Perth Academy Physics Department Higher Physics Particles and Waves Particles and Waves Homework Standard Model 1 Electric Fields and Potential Difference 2 Radioactivity 3 Fusion & Fission 4 The Photoelectric

More information

Experiment objectives: measure the ratio of Planck s constant to the electron charge h/e using the photoelectric effect.

Experiment objectives: measure the ratio of Planck s constant to the electron charge h/e using the photoelectric effect. Chapter 1 Photoelectric Effect Experiment objectives: measure the ratio of Planck s constant to the electron charge h/e using the photoelectric effect. History The photoelectric effect and its understanding

More information

Practical 1P4 Energy Levels and Band Gaps

Practical 1P4 Energy Levels and Band Gaps Practical 1P4 Energy Levels and Band Gaps What you should learn from this practical Science This practical illustrates some of the points from the lecture course on Elementary Quantum Mechanics and Bonding

More information

EEE4106Z Radiation Interactions & Detection

EEE4106Z Radiation Interactions & Detection EEE4106Z Radiation Interactions & Detection 2. Radiation Detection Dr. Steve Peterson 5.14 RW James Department of Physics University of Cape Town steve.peterson@uct.ac.za May 06, 2015 EEE4106Z :: Radiation

More information

1 P a g e h t t p s : / / w w w. c i e n o t e s. c o m / Physics (A-level)

1 P a g e h t t p s : / / w w w. c i e n o t e s. c o m / Physics (A-level) 1 P a g e h t t p s : / / w w w. c i e n o t e s. c o m / Physics (A-level) Electromagnetic induction (Chapter 23): For a straight wire, the induced current or e.m.f. depends on: The magnitude of the magnetic

More information

Instructor: Welcome to. Phys 774: Principles of Spectroscopy. Fall How can we produce EM waves? Spectrum of Electromagnetic Radiation and Light

Instructor: Welcome to. Phys 774: Principles of Spectroscopy. Fall How can we produce EM waves? Spectrum of Electromagnetic Radiation and Light Welcome to Phys 774: Principles of Spectroscopy Fall 2007 Instructor: Andrei Sirenko Associate Professor at the Dept. of Physics, NJIT http://web.njit.edu/~sirenko 476 Tiernan Office hours: After the classes

More information

Classical and Planck picture. Planck s constant. Question. Quantum explanation for the Wein Effect.

Classical and Planck picture. Planck s constant. Question. Quantum explanation for the Wein Effect. 6.1 Quantum Physics. Particle Nature of Light Particle nature of Light Blackbody Radiation Photoelectric Effect Properties of photons Ionizing radiation Radiation damage x-rays Compton effect X-ray diffraction

More information

Higher -o-o-o- Past Paper questions o-o-o- 3.3 Photoelectric

Higher -o-o-o- Past Paper questions o-o-o- 3.3 Photoelectric Higher -o-o-o- Past Paper questions 1991-2010 -o-o-o- 3.3 Photoelectric 1996 Q36 The work function for sodium metal is 2.9x10-19 J. Light of wavelength 5.4x10-7 m strikes the surface of this metal. What

More information

Stimulated Emission Devices: LASERS

Stimulated Emission Devices: LASERS Stimulated Emission Devices: LASERS 1. Stimulated Emission and Photon Amplification E 2 E 2 E 2 hυ hυ hυ In hυ Out hυ E 1 E 1 E 1 (a) Absorption (b) Spontaneous emission (c) Stimulated emission The Principle

More information

X-Rays From Laser Plasmas

X-Rays From Laser Plasmas X-Rays From Laser Plasmas Generation and Applications I. C. E. TURCU CLRC Rutherford Appleton Laboratory, UK and J. B. DANCE JOHN WILEY & SONS Chichester New York Weinheim Brisbane Singapore Toronto Contents

More information

JRE Group of Institutions ASSIGNMENT # 1 Special Theory of Relativity

JRE Group of Institutions ASSIGNMENT # 1 Special Theory of Relativity ASSIGNMENT # 1 Special Theory of Relativity 1. What was the objective of conducting the Michelson-Morley experiment? Describe the experiment. How is the negative result of the experiment interpreted? 2.

More information

CBSE PHYSICS QUESTION PAPER (2005)

CBSE PHYSICS QUESTION PAPER (2005) CBSE PHYSICS QUESTION PAPER (2005) (i) (ii) All questions are compulsory. There are 30 questions in total. Questions 1 to 8 carry one mark each, Questions 9 to 18 carry two marks each, Question 19 to 27

More information

CCD OPERATION. The BBD was an analog delay line, made up of capacitors such that an analog signal was moving along one step at each clock cycle.

CCD OPERATION. The BBD was an analog delay line, made up of capacitors such that an analog signal was moving along one step at each clock cycle. CCDS Lesson 4 CCD OPERATION The predecessor of the CCD was a device called the BUCKET BRIGADE DEVICE developed at the Phillips Research Labs The BBD was an analog delay line, made up of capacitors such

More information

(i) Show that the energy of a single photon is about 3 x J.

(i) Show that the energy of a single photon is about 3 x J. 1(a) A helium-neon laser emits red light of wavelength 6.3 x 10 7 m. (i) Show that the energy of a single photon is about 3 x 10 19 J. [2] The power of the laser beam is 1.0 mw. Show that about 3 x 10

More information

DAY LABORATORY EXERCISE: SPECTROSCOPY

DAY LABORATORY EXERCISE: SPECTROSCOPY AS101 - Day Laboratory: Spectroscopy Page 1 DAY LABORATORY EXERCISE: SPECTROSCOPY Goals: To see light dispersed into its constituent colors To study how temperature, light intensity, and light color are

More information

Experiment #4 Nature of Light: Telescope and Microscope and Spectroscope

Experiment #4 Nature of Light: Telescope and Microscope and Spectroscope Experiment #4 Nature of Light: Telescope and Microscope and Spectroscope In this experiment, we are going to learn the basic principles of the telescope and the microscope that make it possible for us

More information

Laser Basics. What happens when light (or photon) interact with a matter? Assume photon energy is compatible with energy transition levels.

Laser Basics. What happens when light (or photon) interact with a matter? Assume photon energy is compatible with energy transition levels. What happens when light (or photon) interact with a matter? Assume photon energy is compatible with energy transition levels. Electron energy levels in an hydrogen atom n=5 n=4 - + n=3 n=2 13.6 = [ev]

More information

What are the six common sources of light?

What are the six common sources of light? What are the six common sources of light? Common light sources include incandescent, fluorescent, laser, neon, tungsten-halogen, and sodium-vapor bulbs. Objects that give off their own light are luminous.

More information

Phys 2310 Fri. Dec. 12, 2014 Today s Topics. Begin Chapter 13: Lasers Reading for Next Time

Phys 2310 Fri. Dec. 12, 2014 Today s Topics. Begin Chapter 13: Lasers Reading for Next Time Phys 2310 Fri. Dec. 12, 2014 Today s Topics Begin Chapter 13: Lasers Reading for Next Time 1 Reading this Week By Fri.: Ch. 13 (13.1, 13.3) Lasers, Holography 2 Homework this Week No Homework this chapter.

More information

(b) Spontaneous emission. Absorption, spontaneous (random photon) emission and stimulated emission.

(b) Spontaneous emission. Absorption, spontaneous (random photon) emission and stimulated emission. Lecture 10 Stimulated Emission Devices Lasers Stimulated emission and light amplification Einstein coefficients Optical fiber amplifiers Gas laser and He-Ne Laser The output spectrum of a gas laser Laser

More information

Detecting high energy photons. Interactions of photons with matter Properties of detectors (with examples)

Detecting high energy photons. Interactions of photons with matter Properties of detectors (with examples) Detecting high energy photons Interactions of photons with matter Properties of detectors (with examples) Interactions of high energy photons with matter Cross section/attenution length/optical depth Photoelectric

More information

Lab #13: Polarization

Lab #13: Polarization Lab #13: Polarization Introduction In this experiment we will investigate various properties associated with polarized light. We will study both its generation and application. Real world applications

More information

MODERN OPTICS. P47 Optics: Unit 9

MODERN OPTICS. P47 Optics: Unit 9 MODERN OPTICS P47 Optics: Unit 9 Course Outline Unit 1: Electromagnetic Waves Unit 2: Interaction with Matter Unit 3: Geometric Optics Unit 4: Superposition of Waves Unit 5: Polarization Unit 6: Interference

More information

1) Introduction 2) Photo electric effect 3) Dual nature of matter 4) Bohr s atom model 5) LASERS

1) Introduction 2) Photo electric effect 3) Dual nature of matter 4) Bohr s atom model 5) LASERS 1) Introduction 2) Photo electric effect 3) Dual nature of matter 4) Bohr s atom model 5) LASERS 1. Introduction Types of electron emission, Dunnington s method, different types of spectra, Fraunhoffer

More information

EMISSION SPECTROSCOPY

EMISSION SPECTROSCOPY IFM The Department of Physics, Chemistry and Biology LAB 57 EMISSION SPECTROSCOPY NAME PERSONAL NUMBER DATE APPROVED I. OBJECTIVES - Understand the principle of atomic emission spectra. - Know how to acquire

More information

Photoelectric Effect Experiment

Photoelectric Effect Experiment Experiment 1 Purpose The photoelectric effect is a key experiment in modern physics. In this experiment light is used to excite electrons that (given sufficient energy) can escape from a material producing

More information

A beam of coherent monochromatic light from a distant galaxy is used in an optics experiment on Earth.

A beam of coherent monochromatic light from a distant galaxy is used in an optics experiment on Earth. Waves_P2 [152 marks] A beam of coherent monochromatic light from a distant galaxy is used in an optics experiment on Earth. The beam is incident normally on a double slit. The distance between the slits

More information

PRINCIPLES OF PHYSICAL OPTICS

PRINCIPLES OF PHYSICAL OPTICS PRINCIPLES OF PHYSICAL OPTICS C. A. Bennett University of North Carolina At Asheville WILEY- INTERSCIENCE A JOHN WILEY & SONS, INC., PUBLICATION CONTENTS Preface 1 The Physics of Waves 1 1.1 Introduction

More information

Beyond Bohr Model. Wave-particle duality, Probabilistic formulation of quantum physics Chap. 28

Beyond Bohr Model. Wave-particle duality, Probabilistic formulation of quantum physics Chap. 28 Lecture 22-1 Beyond Bohr Model Unfortunately, the classical visualization of the orbiting electron turns out to be wrong even though it still gives us a simple way to think of the atom. Quantum Mechanics

More information

Designing Information Devices and Systems II A. Sahai, J. Roychowdhury, K. Pister Discussion 1A

Designing Information Devices and Systems II A. Sahai, J. Roychowdhury, K. Pister Discussion 1A EECS 16B Spring 2019 Designing Information Devices and Systems II A. Sahai, J. Roychowdhury, K. Pister Discussion 1A 1 Semiconductor Physics Generally, semiconductors are crystalline solids bonded into

More information

Name : Roll No. :.. Invigilator s Signature :.. CS/B.Tech/SEM-2/PH-201/2010 2010 ENGINEERING PHYSICS Time Allotted : 3 Hours Full Marks : 70 The figures in the margin indicate full marks. Candidates are

More information

Modern Physics for Frommies IV The Universe - Small to Large Lecture 4

Modern Physics for Frommies IV The Universe - Small to Large Lecture 4 Fromm Institute for Lifelong Learning University of San Francisco Modern Physics for Frommies IV The Universe - Small to Large Lecture 4 3 February 06 Modern Physics IV Lecture 4 Agenda Administrative

More information

FXA UNIT G485 Module X-Rays. Candidates should be able to : I = I 0 e -μx

FXA UNIT G485 Module X-Rays. Candidates should be able to : I = I 0 e -μx 1 Candidates should be able to : HISTORY Describe the nature of X-rays. Describe in simple terms how X-rays are produced. X-rays were discovered by Wilhelm Röntgen in 1865, when he found that a fluorescent

More information

Chapter 5 Electrons In Atoms

Chapter 5 Electrons In Atoms Chapter 5 Electrons In Atoms 5.1 Revising the Atomic Model 5.2 Electron Arrangement in Atoms 5.3 Atomic Emission Spectra and the Quantum Mechanical Model 1 Copyright Pearson Education, Inc., or its affiliates.

More information

Advanced Optical Communications Prof. R. K. Shevgaonkar Department of Electrical Engineering Indian Institute of Technology, Bombay

Advanced Optical Communications Prof. R. K. Shevgaonkar Department of Electrical Engineering Indian Institute of Technology, Bombay Advanced Optical Communications Prof. R. K. Shevgaonkar Department of Electrical Engineering Indian Institute of Technology, Bombay Lecture No. # 15 Laser - I In the last lecture, we discussed various

More information

LECTURE # 17 Modern Optics Matter Waves

LECTURE # 17 Modern Optics Matter Waves PHYS 270-SPRING 2011 LECTURE # 17 Modern Optics Matter Waves April 5, 2011 1 Spectroscopy: Unlocking the Structure of Atoms There are two types of spectra, continuous spectra and discrete spectra: Hot,

More information

Fall 2014 Nobby Kobayashi (Based on the notes by E.D.H Green and E.L Allen, SJSU) 1.0 Learning Objectives

Fall 2014 Nobby Kobayashi (Based on the notes by E.D.H Green and E.L Allen, SJSU) 1.0 Learning Objectives University of California at Santa Cruz Electrical Engineering Department EE-145L: Properties of Materials Laboratory Lab 7: Optical Absorption, Photoluminescence Fall 2014 Nobby Kobayashi (Based on the

More information

EE 5344 Introduction to MEMS CHAPTER 5 Radiation Sensors

EE 5344 Introduction to MEMS CHAPTER 5 Radiation Sensors EE 5344 Introduction to MEMS CHAPTER 5 Radiation Sensors 5. Radiation Microsensors Radiation µ-sensors convert incident radiant signals into standard electrical out put signals. Radiant Signals Classification

More information

2 Fundamentals of Flash Lamp Annealing of Shallow Boron-Doped Silicon

2 Fundamentals of Flash Lamp Annealing of Shallow Boron-Doped Silicon 2 Fundamentals of Flash Lamp Annealing of Shallow Boron-Doped Silicon MSA of semiconductors is usually performed using flash lamps. It has been shown that FLA holds the balance between effective dopant

More information

LASERS AGAIN? Phys 1020, Day 17: Questions? LASERS: Next Up: Cameras and optics Eyes to web: Final Project Info

LASERS AGAIN? Phys 1020, Day 17: Questions? LASERS: Next Up: Cameras and optics Eyes to web: Final Project Info LASERS AGAIN? Phys 1020, Day 17: Questions? LASERS: 14.3 Next Up: Cameras and optics Eyes to web: Final Project Info 1 Group Exercise Your pennies will simulate a two state atom; tails = ground state,

More information

Photonic Devices. Light absorption and emission. Transitions between discrete states

Photonic Devices. Light absorption and emission. Transitions between discrete states Light absorption and emission Photonic Devices Transitions between discrete states Transition rate determined by the two states: Fermi s golden rule Absorption and emission of a semiconductor Vertical

More information

OPSE FINAL EXAM Fall 2015 YOU MUST SHOW YOUR WORK. ANSWERS THAT ARE NOT JUSTIFIED WILL BE GIVEN ZERO CREDIT.

OPSE FINAL EXAM Fall 2015 YOU MUST SHOW YOUR WORK. ANSWERS THAT ARE NOT JUSTIFIED WILL BE GIVEN ZERO CREDIT. CLOSED BOOK. Equation Sheet is provided. YOU MUST SHOW YOUR WORK. ANSWERS THAT ARE NOT JUSTIFIED WILL BE GIVEN ZERO CREDIT. ALL NUMERICAL ANSERS MUST HAVE UNITS INDICATED. (Except dimensionless units like

More information

Two-electron systems

Two-electron systems Two-electron systems Laboratory exercise for FYSC11 Instructor: Hampus Nilsson hampus.nilsson@astro.lu.se Lund Observatory Lund University September 12, 2016 Goal In this laboration we will make use of

More information

Introduction to Plasma

Introduction to Plasma What is a plasma? The fourth state of matter A partially ionized gas How is a plasma created? Energy must be added to a gas in the form of: Heat: Temperatures must be in excess of 4000 O C Radiation Electric

More information

Gaetano L Episcopo. Scanning Electron Microscopy Focus Ion Beam and. Pulsed Plasma Deposition

Gaetano L Episcopo. Scanning Electron Microscopy Focus Ion Beam and. Pulsed Plasma Deposition Gaetano L Episcopo Scanning Electron Microscopy Focus Ion Beam and Pulsed Plasma Deposition Hystorical background Scientific discoveries 1897: J. Thomson discovers the electron. 1924: L. de Broglie propose

More information

PHYSICS 2005 (Delhi) Q3. The power factor of an A.C. circuit is 0.5. What will be the phase difference between voltage and current in this circuit?

PHYSICS 2005 (Delhi) Q3. The power factor of an A.C. circuit is 0.5. What will be the phase difference between voltage and current in this circuit? General Instructions: 1. All questions are compulsory. 2. There is no overall choice. However, an internal choke has been pro vided in one question of two marks, one question of three marks and all three

More information