Принципы нанометрологии (Раздаточные материалы от преподавателя), страница 4

These include: Mr James Claverley, Dr Alex Cuenat, Dr StuartDavidson, Mr David Flack, Prof Mark Gee, Mr Claudiu Giusca, Dr PeterHarris, Mr Chris Jones, Mr Andy Knott, Dr Andrew Lewis, Dr Simon Reillyand Dr Andrew Yacoot. Especial thanks are due to Mr Julian Game for all hismagical work with the superb figures.xvxviAcknowledgementsI must also thank Dr Nigel Hollingsworth (Key Technologies InnovationsInternational) for all his support during the writing of the book.This book is dedicated to the late Prof Albert Franks, who was my firstmanager at NPL and gave me a great deal of inspiration for this field ofresearch. Thank you Albert.I wish to express thanks to my parents and sisters; they are, after all, theones I wish to please most. Also I would like to mention my son Marcus,whom I love dearly.FiguresFigure 2.1Figure 2.2Figure 2.3Figure 2.4Figure 2.5Figure 2.6Figure 2.7Figure 2.8Figure 2.9Figure 3.1Figure 3.2Figure 3.3Figure 3.4Figure 3.5Figure 3.6Figure 3.7Figure 4.1Figure 4.2Figure 4.3Figure 4.4Figure 4.5Figure 4.6Figure 4.7An ancient Egyptian cubit (a standard of mass is alsoshown) .......................................................................................

6Metal bar length standards (gauge blocks and length bars) ..... 8An iodine-stabilised helium-neon laser based at NPL, UK ... 10Kilogram 18 held at the NPL, UK .......................................... 11Energy levels in the He-Ne gas laser for 632.8 nmradiation .................................................................................. 24Schema of an iodine-stabilised He-Ne laser .......................... 27Frequency and intensity profiles in a two-modeHe-Ne laser ............................................................................. 27Magnetic splitting of neon – g is the Landé g factor,m the Bohr magneton ..............................................................

29Calibration scheme for Zeeman-stabilised laser.................... 30(a) A Type I Kelvin clamp, (b) a Type II Kelvin clamp ............ 38A single degree of freedom motion device.............................. 39Effects of Abbe error on an optical length measurement ...... 40Mutual compression of a sphere on a plane .......................... 42Kevin Lindsey with the Tetraform grinding machine ............ 47Measured vertical amplitude spectrum on a ‘noisy’(continuous line) and a ‘quiet’ (dotted line) site [29] .............

48Damped transmissibility, T, as a function of frequencyratio (u/u0)............................................................................... 50Definition of the length of a gauge block ............................... 57A typical gauge block wrung to a platen ................................. 58Amplitude division in a Michelson/Twyman-Greeninterferometer..........................................................................

60Intensity as a function of phase for different visibility .......... 61Intensity distribution for a real light source .......................... 62Illustration of the effect of a limited coherence lengthfor different sources ................................................................ 63Schema of the original Michelson interferometer ................. 64xviixviiiFiguresFigure 4.8 Schema of a Twyman-Green interferometer ..........................

65Figure 4.9 The Fizeau interferometer ...................................................... 66Figure 4.10 Typical interference pattern of a flat surface in aFizeau interferometer .............................................................. 67Figure 4.11 Schema of a Jamin interferometer..........................................

69Figure 4.12 Schema of a Mach-Zehnder interferometer ........................... 69Figure 4.13 Schematic of the Fabry-Pérot interferometer ......................... 70Figure 4.14 Transmittance as a function of distance, L, for variousreflectances .............................................................................. 71Figure 4.15 Possible definition of a mechanical gauge block length ........ 72Figure 4.16 Schema of a gauge block interferometer containinga gauge block ...........................................................................

73Figure 4.17 Theoretical interference pattern of a gauge blockon a platen ............................................................................... 74Figure 4.18 Method for determining a surface and phase changecorrection................................................................................. 79Figure 5.1 Homodyne interferometer configuration ............................... 87Figure 5.2 Heterodyne interferometer configuration............................... 88Figure 5.3 Optical arrangement to double pass aMichelson interferometer ....................................................... 90Figure 5.4 Schema of a differential plane mirror interferometer ............ 91Figure 5.5 Cosine error with an interferometer ......................................

94Figure 5.6 Schema of an angular interferometer ..................................... 98Figure 5.7 A typical capacitance sensor set-up ........................................ 99Figure 5.8 Schematic of an LVDT probe ............................................... 101Figure 5.9 Error characteristic of an LVDT probe ................................. 102Figure 5.10 Schema of an optical encoder ............................................... 103Figure 5.11 Total internal reflectance in an optical fibre ........................

104Figure 5.12 End view of bifurcated optical fibre sensors,(a) hemispherical, (b) random and (c) fibre pair ................... 105Figure 5.13 Bifurcated fibre optic sensor components ............................ 106Figure 5.14 Bifurcated fibre optic sensor response curve ........................ 106Figure 5.15 Schema of an X-ray interferometer ......................................

109Figure 5.16 Schema of a combined optical and X-ray interferometer .... 110Figure 6.1 Amplitude-wavelength space depicting the operatingregimes for common instruments ........................................ 117Figure 6.2 The original Talysurf instrument (courtesy ofTaylor Hobson) ...................................................................... 119Figure 6.3 Example of the result of a profile measurement .................. 120Figure 6.4 Profiles showing the same Ra with differingheight distributions ............................................................... 122FiguresFigure 6.5Figure 6.6Figure 6.7Figure 6.8Figure 6.9Figure 6.10Figure 6.11Figure 6.12Figure 6.13Figure 6.14Figure 6.15Figure 6.16Figure 6.17Figure 6.18Figure 6.19Figure 6.20Figure 6.21Figure 6.22Figure 6.23Figure 6.24Figure 6.25Figure 6.26Figure 6.27Figure 6.28A profile taken from a 3D measurement shows thepossible ambiguity of 2D measurement andcharacterisation .....................................................................

122Schema of a typical stylus instrument ................................. 123Damage to a brass surface due to a high stylus force .......... 124Numerical aperture of a microscope objective lens ............. 128Example of the batwing effect when measuringa step using a coherence scanning interferometer ............... 131Over-estimation of surface roughness due tomultiple scattering in vee-grooves ........................................ 132Principle of a laser triangulation sensor ............................... 133Confocal set-up with (a) object in focus and (b) objectout of focus ............................................................................ 135Demonstration of the confocal effect on a piece of paper:(a) microscopic bright field image (b) confocal image.The contrast of both images has been enhanced fora better visualisation .............................................................

136Schematic representation of a confocal curve.If the surface is in focus (position 0) the intensityhas a maximum .................................................................... 136Schema of a Nipkow disk. The pinholes rotate throughthe intermediate image and sample the whole area withinone revolution ....................................................................... 137Schema of a confocal microscope using a Nipkow disk ...... 137Chromatic confocal depth discrimination ........................... 139Schema of a point autofocus instrument ............................. 140Principle of point autofocus operation .................................

141Schema of a focus variation instrument .............................. 142Schema of a phase-shifting interferometer .......................... 144Schematic diagram of a Mirau objective .............................. 145Schematic diagram of a Linnik objective ............................. 146Schematic diagram of DHM with beam-splitter (BS),mirrors (M), condenser (C), microscope objective (MO) andlens in the reference arm (RL) used to perform a referencewave curvature similar to the object wave curvature (someDHM use the same MO in the object wave) ........................ 148Schema of a coherence scanning interferometer .................