Optical Methods of Measurement Wholefield TechniquesSecond Edition CRC.pdf

“DK4217_C000.tex”page i#115/5/200910:56“DK4217_C000.tex”page ii#215/5/200910:56“DK4217_C000.tex”page iii#315/5/200910:56“DK4217_C000.tex”page iv#415/5/200910:56“DK4217_C000.tex”page v#515/5/200910:56“DK4217_C000.tex”page vi#615/5/200910:56“DK4217_C000.tex”page vii#715/5/200910:56“DK4217_C000.tex”page viii#815/5/200910:56“DK4217_C000.tex”page ix#915/5/200910:56“DK4217_C000.tex”page x#1015/5/200910:56“DK4217_C000.tex”page xi#1115/5/200910:56ContentsFrom the Series Editor.xixPreface.xxiPreface to First Edition.xxiiiAuthor.xxvChapter 1Waves and Beams.11.1The Wave Equation.11.2Plane Waves.21.3Spherical Waves.21.4Cylindrical Waves.21.5Waves as Information Carriers.31.5.1Amplitude/Intensity-Based Sensors.41.5.2Sensors Based on Phase Measurement.41.5.3Sensors Based on Polarization.51.5.4Sensors Based on Frequency Measurement.51.5.5Sensors Based on Change of Direction.51.6The Laser Beam.51.7The Gaussian Beam.61.8ABCD MatrixApplied to Gaussian Beams.81.8.1Propagation in Free Space.91.8.2Propagation through a Thin Lens.101.8.3Mode Matching.121.9Nondiffracting BeamsBessel Beams.121.10Singular Beams.13Bibliography.17Additional Reading.17Chapter 2Optical Interference.192.1Introduction.192.2Generation of Coherent Waves.202.2.1Interference by Division of Wavefront.202.2.2Interference by Division ofAmplitude.202.3Interference between Two Plane Monochromatic Waves.212.3.1Young s Double-Slit Experiment.222.3.2Michelson Interferometer.242.4Multiple-Beam Interference.25xi“DK4217_C000.tex”page xii#1215/5/200910:56xiiContents2.4.1Multiple-Beam Interference:Divisionof Wavefront.252.4.2Multiple-Beam Interference:DivisionofAmplitude.272.4.2.1 Interference Pattern in Transmission.272.4.2.2 Interference Pattern in Reflection.292.5Interferometry.292.5.1Dual-Wavelength Interferometry.302.5.2White Light Interferometry.312.5.3Heterodyne Interferometry.312.5.4Shear Interferometry.322.5.5Polarization Interferometers.332.5.6Interference Microscopy.342.5.7Doppler Interferometry.362.5.8Fiber-Optic Interferometers.372.5.9Phase-Conjugation Interferometers.38Bibliography.39Additional Reading.40Chapter 3Diffraction.433.1Fresnel Diffraction.433.2Fraunhofer Diffraction.443.3Action of a Lens.453.4Image Formation and Fourier Transformation by a Lens.453.4.1Image Formation.473.4.2Fourier Transformation.473.5Optical Filtering.493.6Optical Components in Optical Metrology.503.6.1Reflective Optical Components.503.6.2Refractive Optical Components.503.6.3Diffractive Optical Components.523.6.3.1 Sinusoidal Grating.553.6.4Phase Grating.563.6.5Diffraction Efficiency.573.7Resolving Power of Optical Systems.57Bibliography.58Chapter 4Phase-Evaluation Methods.594.1Interference Equation.594.2Fringe Skeletonization.604.3Temporal Heterodyning.614.4Phase-Sampling Evaluation:Quasi-Heterodyning.624.5Phase-Shifting Method.634.6Phase-Shifting with Unknownbut Constant Phase-Step.634.7Spatial Phase-Shifting.66“DK4217_C000.tex”page xiii#1315/5/200910:56Contentsxiii4.8Methods of Phase-Shifting.684.8.1PZT-Mounted Mirror.684.8.2Tilt of Glass Plate.694.8.3Rotation of Polarization Component.704.8.4Motion of a Diffraction Grating.724.8.5Use of a CGH Written on a SpatialLight Modulator.724.8.6Special Methods.724.9Fourier Transform Method.724.10Spatial Heterodyning.73Bibliography.75Additional Reading.75Chapter 5Detectors and Recording Materials.795.1Detector Characteristics.795.2Detectors.805.2.1Photoconductors.805.2.2Photodiodes.815.2.3Photomultiplier Tube.845.3Image Detectors.845.3.1Time-Delay and Integration Mode ofOperation.895.4Recording Materials.895.4.1Photographic Films and Plates.905.4.2Dichromated Gelatin.945.4.3Photoresists.955.4.4Photopolymers.955.4.5Thermoplastics.965.4.6Photochromics.965.4.7Ferroelectric Crystals.97Bibliography.98Additional Reading.98Chapter 6Holographic Interferometry.1016.1Introduction.1016.2Hologram Recording.1026.3Reconstruction.1036.4Choice ofAngle of Reference Wave.1046.5Choice of Reference Wave Intensity.1056.6Types of Holograms.1056.7Diffraction Efficiency.1056.8ExperimentalArrangement.1056.8.1Lasers.1066.8.2Beam-Splitters.1076.8.3Beam-Expanders.1076.8.4Object-Illumination Beam.107“DK4217_C000.tex”page xiv#1415/5/200910:56xivContents6.8.5Reference Beam.1076.8.6Angle between Object and Reference Beams.1086.9Holographic Recording Materials.1086.10Holographic Interferometry.1086.10.1Real-Time HI.1086.10.2Double-Exposure HI.1096.10.3Time-Average HI.1106.10.4Real-Time,Time-Average HI.1156.11Fringe Formation and Measurement ofDisplacementVector.1156.12Loading of the Object.1166.13Measurement ofVery SmallVibrationAmplitudes.1176.14Measurement of Large VibrationAmplitudes.1176.14.1Frequency Modulation of Reference Wave.1176.14.2Phase Modulation of Reference Beam.1196.15Stroboscopic Illumination/Stroboscopic HI.1206.16Special Techniques in Holographic Interferometry.1216.16.1Two-Reference-Beam HI.1216.16.2Sandwich HI.1236.16.3Reflection HI.1256.17Extending the Sensitivity of HI.1276.17.1Heterodyne HI.1276.18Holographic Contouring/Shape Measurement.1296.18.1Dual-Wavelength Method.1296.18.2Dual-Refractive Index Method.1316.18.3Dual-Illumination Method.1326.19Holographic Photoelasticity.1326.20Digital Holography.1326.20.1Recording.1326.20.2Reconstruction.1336.21Digital Holographic Interferometry.135Bibliography.136Additional Reading.137Chapter 7Speckle Metrology.1497.1The Speckle Phenomenon.1497.2Average Speckle Size.1497.2.1Objective Speckle Pattern.1507.2.2Subjective Speckle Pattern.1507.3Superposition of Speckle Patterns.1517.4Speckle Pattern and Object Surface Characteristics.1527.5Speckle Pattern and Surface Motion.1527.5.1Linear Motion in the Plane of the Surface.1527.5.2Out-of-Plane Displacement.1527.5.3Tilt of the Object.1537.6Speckle Photography.155“DK4217_C000.tex”page xv#1515/5/200910:56Contentsxv7.7Methods of Evaluation.1587.7.1Pointwise Filtering.1587.7.2Wholefield Filtering.1607.7.3Fourier Filtering:Measurement of Out-of-PlaneDisplacement.1617.8Speckle Photography withVibrating Objects:In-Plane Vibration.1617.9Sensitivity of Speckle Photography.1627.10Particle Image Velocimetry.1627.11White-Light Speckle Photography.1627.12Shear Speckle Photography.1637.13Speckle Interferometry.1647.14Correlation Coefficient in Speckle Interferometry.1677.15Out-of-Plane Speckle Interferometer.1687.16In-Plane Measurement:Duffy s Method.1697.17Filtering.1717.17.1Fringe Formation.1717.18Out-of-Plane Displacement Measurement.1737.19Simultaneous Measurement of Out-of-Plane and In-PlaneDisplacement Components.1747.20Other Possibilities forAperturing the Lens.1757.21Duffy sArrangement:Enhanced Sensitivity.1767.22Speckle InterferometryShape Measurement/Contouring.1777.23Speckle Shear Interferometry.1777.23.1The Meaning of Shear.1777.24Methods of Shearing.1787.25Theory of Speckle Shear Interferometry.1807.26Fringe Formation.1817.26.1The Michelson Interferometer.1817.26.2TheApertured LensArrangement.1827.27Shear Interferometry without Influence of the In-PlaneComponent.1837.28Electronic Speckle Pattern Interferometry.1837.28.1Out-of-Plane Displacement Measurement.1847.28.2In-Plane Displacement Measurement.1857.28.3VibrationAnalysis.1857.28.4Measurement on Small Objects.1867.28.5Shear ESPI Measurement.1877.29Contouring in ESPI.1877.29.1Change of Direction of Illumination.1887.29.2Change of Wavelength.1897.29.3Change of Medium Surrounding the Object.1897.29.4Tilt of the Object.1897.30Special Techniques.1897.30.1Use of Retro-Reflective Paint.189“DK4217_C000.tex”page xvi#1615/5/200910:56xviContents7.31Spatial Phase-Shifting.190Bibliography.191Additional Reading.191Chapter 8Photoelasticity.2018.1Superposition of Two-Plane Polarized Waves.2018.2Linear Polarization.2028.3Circular Polarization.2038.4Production of Polarized Light.2038.4.1Reflection.2048.4.2Refraction.2048.4.3Double Refraction.2048.4.3.1 Phase Plates.2058.4.3.2 Quarter-Wave Plate.2068.4.3.3 Half-Wave Plate.2068.4.3.4 Compensators.2068.4.4Dichroism.2078.4.5Scattering.2078.5Malus s Law.2078.6The Stress-Optic Law.2078.7The Strain-Optic Law.2098.8Methods ofAnalysis.2108.8.1Plane Polariscope.2108.8.2Circular Polariscope.2128.9Evaluation Procedure.2168.10Measurement of Fractional Fringe Order.2178.10.1Tardy s Method.2178.11Phase-Shifting.2208.11.1Isoclinics Computation.2208.11.2Computation of Isochromatics.2218.12Birefringent Coating Method:Reflection Polariscope.2228.13Holophotoelasticity.2238.13.1Single-Exposure Holophotoelasticity.2248.13.2Double-Exposure Holophotoelasticity.2258.14Three-Dimensional Photoelasticity.2298.14.1The Frozen-Stress Method.2298.14.2Scattered-Light Photoelasticity.2308.15Examination of the Stressed Model inScattered Light.2308.15.1Unpolarized Incident Light.2308.15.2Linearly Polarized Incident Beam.232Bibliography.233Additional Reading.234Chapter 9The Moir Phenomenon.2399.1Introduction.239“DK4217_C000.tex”page xvii#1715/5/200910:56Contentsxvii9.2The Moir Fringe Pattern between TwoLinear Gratings.2399.2.1a?=b but =0.2419.2.2a=b but?=0.2419.3The Moir Fringe Pattern between a Linear Gratingand a Circular Grating.2429.4Moir between Sinusoidal Gratings.2439.5Moir between Reference and Deformed Gratings.2459.6Moir Pattern with Deformed Sinusoidal Grating.2469.6.1Multiplicative Moir Pattern.2479.6.2Additive Moir Pattern.2479.7Contrast Improvement of theAdditive Moir Pattern.2489.8Moir Phenomenon for Measurement.2489.9Measurement of In-Plane Displacement.2489.9.1Reference and Measurement Gratings of EqualPitch andAligned Parallel toEach Other.2489.9.2Two-Dimensional In-Plane DisplacementMeasurement.2499.9.3High-Sensitivity In-Plane DisplacementMeasurement.2519.10Measurement of Out-of-Plane Componentand Contouring.2539.10.1The Shadow Moir Method.2549.10.1.1Parallel Illumination and ParallelObservation.2549.10.1.2Spherical-Wave Illumination andCamera at Finite Distance.2559.10.2Automatic Shape Determination.2579.10.3Projection Moir.2579.10.4Light-Line Projection with TDI Modeof Operation of CCD Camera.2609.10.5Coherent Projection Method.2629.10.5.1Interference between TwoCollimated Beams.2629.10.5.2Interference between TwoSpherical Waves.2639.10.6Measurement ofVibrationAmplitudes.2649.10.7Reflection Moir Method.2659.11Slope Determination for Dynamic Events.2679.12Curvature Determination for Dynamic Events.2689.13Surface Topography with Reflection Moir Method.2699.14Talbot Phenomenon.2719.14.1Talbot Effect in Collimated Illumination.2729.14.2Cut-Off Distance.2739.14.3Talbot Effect in Noncollimated Illumination.273“DK4217_C000.tex”page xviii#1815/5/200910:56xviiiContents9.14.4Talbot Effect for Measurement.2749.14.4.1Temperature Measurement.2749.14.4.2Measurement of the Focal Lengthof a Lens and the Long Radius ofCurvature of a Surface.275Bibliography.275Additional Reading.275Index.283“DK4217_C000.tex”page xix#1915/5/200910:56From the Series EditorOver the last 20 years,optical science and engineering has emerged as a disciplinein its own right.This has occurred with the realization that we are dealing withan integrated body of knowledge that has resulted in optical science,engineering,and technology becoming an enabling discipline that can be applied to a variety ofscientific,industrial,commercial,andmilitaryproblemstoproduceoperatingdevicesand hardware systems.This book series is a testament to the truth of the precedingstatement.Quality control and the testing have become essential tools in modern industryand modern laboratory processes.Optical methods of measurement have providedmany of the essential techniques of current practice.This current volume on OpticalMethods of Measurement emphasizes wholefield measurement methods as opposedto point measurement,that is,sensing a field all at once and then mapping that fieldfor the parameter or parameters under consideration as contrasted to building upthat field information by a time series of point-by-point determinations.The initialoutput of these wholefield systems of measurement is often a fringe pattern that isthenprocessed.Therequiredfringesareformedbydirectinterferometry,holographicinterferometry,phase-shiftingmethods,heterodyning,specklepatterninterferometry,and moir techniques.The methods described here are applicable to many measurement scenarios,although the examples focus on modern experimental mechanics.Since this volumecovers the variety of techniques available and their range of applicability togetherwith their sensitivity and accuracy as determined by the underlying principle,thereader will find these pages an excellent practice guide of wholefield measurementas well as a desk reference volume.Brian J.Thompsonxix“DK4217_C000.tex”page xx#2015/5/200910:56“DK4217_C000.tex”page xxi#2115/5/200910:56PrefaceMany good ideas originated from several of my professional colleagues that haveconsiderably improved the book.I would like to thank Prof.Osten from StuttgartUniversity and Professors Hinsch and Helmers from the University of Oldenburg forprovidingnumerouscontributionstothecontentsofthebook.Ioweagreatdealtomycolleagues Prof.M.P.Kothiyal,Prof.Chandra Shakher,and Dr.N.Krishna Mohanfor their help and support at various stages.Since the phenomenon of interference is central to many techniques of measure-ment,I have introduced a chapter on“Optical Interference.”There have been severaladditions like the non-diffracting beam and singular beam with their metrologicalapplications.Bibliography and additional reading have been expanded.The bookcontains references to 103 books,827 journal papers,and 130 figures.Revision of this book was originally slated for late 2005;however,administrativeresponsibilities prevented this.It is only through the persistent efforts by the staffof Taylor&Francis that the revision finally materialized.I would therefore like toexpress my sincere thanks to Jessica Vakili and Catherine Giacari for keeping myinterest in the book alive.Rajpal S.Sirohixxi“DK4217_C000.tex”page xxii#2215/5/200910:56“DK4217_C000.tex”page xxiii#2315/5/200910:56Preface to First EditionOptical techniques of measurement are among the most sensitive known today.Inaddition,they are noncontact,noninvasive,and fast.In recent years,the use of opticaltechniquesformeasurementhavedramaticallyincreased,andapplicationsrangefromdetermining the topography of landscapes to checking the roughness of polishedsurfaces.Any of the characteristics of a light waveamplitude,phase,length,frequency,polarization,and direction of propagationcan be modulated by the measurand.Ondemodulation,the value of the measurand at a spatial point and at a particular timeinstant can be obtained.Optical methods can effect measurement at discrete pointsor over the wholefield with extremely fine spatial resolution.For many applications,wholefield measurements are preferred.This book contains a wealth of information on wholefield measurement methods,particularly those employed frequently on modern experimental mechanics since thevariablethatisnormallymonitoredisdisplacement.Thus,themethodscanbeusedtodeterminesurfacedeformation,strains,andstresses.Byextension,theycanbeappliedin the nondestructive evaluatio