Table Of ContentAdvances in Optical Form and
Coordinate Metrology
IOP Series in Emerging Technologies in Optics and Photonics
Series Editor
R Barry Johnson a Senior Research Professor at Alabama A&M
University, has been involved for over 50 years in lens design,
optical systems design, electro-optical systems engineering, and
photonics. He has been a faculty member at three academic
institutions engaged in optics education and research, employed
by a number of companies, and provided consulting services.
DrJohnsonisanIOPFellow,SPIEFellowandLifeMember,OSAFellow,andwas
the 1987 President of SPIE. He serves on the editorial board of Infrared Physics &
Technology and Advances in Optical Technologies. Dr Johnson has been awarded
manypatents,haspublishednumerouspapersandseveralbooksandbookchapters,
andwasawardedthe2012OSA/SPIEJosephWGoodmanBookWritingAwardfor
LensDesignFundamentals,SecondEdition.Heisaperennialco-chairoftheannual
SPIE Current Developments in Lens Design and Optical Engineering Conference.
Foreword
Untilthe1960s,thefieldofopticswasprimarilyconcentratedintheclassicalareasof
photography, cameras, binoculars, telescopes, spectrometers, colorimeters, radio-
meters,etc.Inthelate1960s,opticsbegantoblossomwiththeadventofnewtypesof
infrareddetectors,liquidcrystaldisplays(LCD),lightemittingdiodes(LED),charge
coupled devices (CCD), lasers, holography, fiber optics, new optical materials,
advances in optical and mechanical fabrication, new optical design programs, and
many more technologies.With thedevelopment ofthe LED,LCD, CCD and other
electo-optical devices, the term ‘photonics’ came into vogue in the 1980s to describe
thescienceofusinglightindevelopmentofnewtechnologiesandtheperformanceof
amyriadofapplications.Today,opticsandphotonicsaretrulypervasivethroughout
societyandnewtechnologiesarecontinuingtoemerge.Theobjectiveofthisseriesis
to provide students, researchers, and those who enjoy self-teaching with a wide-
ranging collection of books that each focus on a relevant topic in technologies and
applicationofopticsand photonics.Thesebookswill provideknowledgetoprepare
thereadertobebetterabletoparticipateintheseexcitingareasnowandinthefuture.
The title of this series is Emerging Technologies in Optics and Photonics where
‘emerging’ is taken to mean ‘coming into existence,’ ‘coming into maturity,’ and
‘coming into prominence.’ IOP Publishing and I hope that you find this Series of
significant value to you and your career.
Advances in Optical Form and
Coordinate Metrology
Edited by
Richard Leach
Manufacturing Metrology Team, Faculty of Engineering, University of Nottingham,
Nottingham, UK
IOP Publishing, Bristol, UK
ªIOPPublishingLtd2020
Allrightsreserved.Nopartofthispublicationmaybereproduced,storedinaretrievalsystem
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PermissiontomakeuseofIOPPublishingcontentotherthanassetoutabovemaybesought
[email protected].
RichardLeachhasassertedhisrighttobeidentifiedastheauthorofthisworkinaccordancewith
sections77and78oftheCopyright,DesignsandPatentsAct1988.
ISBN 978-0-7503-2524-0(ebook)
ISBN 978-0-7503-2522-6(print)
ISBN 978-0-7503-2525-7(myPrint)
ISBN 978-0-7503-2523-3(mobi)
DOI 10.1088/978-0-7503-2524-0
Version:20201201
IOPebooks
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fromtheBritishLibrary.
PublishedbyIOPPublishing,whollyownedbyTheInstituteofPhysics,London
IOPPublishing,TempleCircus,TempleWay,Bristol,BS16HG,UK
USOffice:IOPPublishing,Inc.,190NorthIndependenceMallWest,Suite601,Philadelphia,
PA19106,USA
Contents
Preface x
Editor biography xi
List of contributors xii
1 Terms, definitions and standards 1-1
Richard Leach
1.1 Introduction 1-1
1.2 Surface and coordinate terms and definitions 1-2
1.3 General metrology terms and definitions 1-3
1.4 Specification standards for coordinate metrology 1-6
1.4.1 Coordinate metrology standards 1-6
Acknowledgements 1-7
References 1-7
2 State-of-the-art in point cloud analysis 2-1
Sofia Catalucci and Nicola Senin
2.1 Introduction 2-1
2.1.1 Mathematical representation of 3D point clouds 2-2
2.1.2 Common 3D point cloud file formats 2-2
2.1.3 Point cloud transformations 2-3
2.2 Extracting properties and organising information in point clouds 2-7
2.2.1 Convex hull and bounding boxes 2-7
2.2.2 Centroid and principal axes of a point cloud 2-8
2.2.3 Spatial subdivision of point clouds 2-10
2.3 Point cloud pre-processing 2-14
2.3.1 Point cloud simplification, decimation and resampling 2-15
2.3.2 Elimination of isolated points and noise reduction 2-16
2.3.3 Triangle meshes and conversion to/from point clouds 2-18
2.4 Point features and partitioning 2-20
2.4.1 Point normals 2-20
2.4.2 Point curvatures 2-21
2.4.3 Partitioning and segmentation 2-23
2.5 Point cloud fitting 2-25
2.5.1 Fitting methods 2-25
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2.6 Registration of point clouds 2-29
2.6.1 Registration based on external references or based on 2-32
matching landmarks
2.6.2 The absolute orientation problem 2-32
2.6.3 Alignment by means of principal component analysis 2-33
2.6.4 RANSAC alignment 2-34
2.6.5 Alignment by iterative closest points 2-36
2.6.6 Landmark matching and alignment using similarity metrics 2-38
2.7 Measurement uncertainty in point cloud surface data 2-38
2.7.1 Approaches to the estimation of measurement uncertainty 2-39
2.7.2 Uncertainty associated with point clouds 2-41
2.8 Conclusions 2-42
References 2-43
3 Laser triangulation 3-1
Mohammed A Isa, Samanta Piano and Richard Leach
3.1 Laser triangulation 3-1
3.2 Laser triangulation sensors 3-3
3.3 Laser triangulation measurement dependence on surface properties 3-5
3.3.1 Measurement uncertainty limit 3-6
3.3.2 Surface reflectance perspective 3-7
3.3.3 Measurement dependence on surface form 3-11
3.4 Laser triangulation systems 3-13
3.4.1 Extension of a point based laser triangulation sensor 3-13
3.4.2 Point measurement systems 3-15
3.4.3 Profile measurement systems 3-17
3.4.4 Surface measurement systems 3-19
3.4.5 Advanced laser triangulation systems 3-21
3.5 Working process of laser triangulation 3-24
3.5.1 Characterisation of intrinsic parameters 3-24
3.5.2 Characterisation of extrinsic parameters 3-25
3.5.3 Pre-calibration of laser triangulation systems 3-25
3.5.4 Scanning path planning 3-27
3.5.5 Image pre-processing 3-27
3.5.6 Laser feature extraction 3-28
3.5.7 Refinement and postprocessing 3-30
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3.6 Application of laser triangulation measurements 3-31
3.6.1 Application of laser triangulation in emerging 3-31
manufacturing methods
3.6.2 Application for geometric inspection 3-33
3.6.3 Application of 3D reconstructed models 3-34
3.7 Conclusions 3-35
References 3-36
4 Close-range photogrammetry 4-1
Danny Sims-Waterhouse, Richard Leach and Samanta Piano
4.1 Introduction 4-1
4.1.1 Modern photogrammetry 4-2
4.1.2 Camera projection theory 4-2
4.1.3 The pinhole camera model 4-3
4.1.4 Distortion modelling 4-5
4.2 Characterisation and calibration 4-6
4.2.1 Camera characterisation 4-6
4.2.2 Linear techniques 4-7
4.2.3 Non-linear methods 4-8
4.2.4 Self-calibration 4-11
4.3 System calibration 4-11
4.3.1 Arbitrary scale 4-11
4.4 Image acquisition 4-12
4.4.1 Depth of field 4-12
4.4.2 Imaging procedure optimisation 4-14
4.5 Summary 4-16
References 4-16
5 Digital fringe projection profilometry 5-1
Rui Chen, Jing Xu and Song Zhang
5.1 Introduction 5-1
5.2 Fringe pattern generation methods 5-1
5.2.1 Conventional fringe generation methods 5-1
5.2.2 Digital binary defocusing techniques 5-2
5.2.3 New fringe pattern generation methods 5-3
5.3 Fringe analysis 5-4
5.3.1 Conventional fringe analysis techniques 5-4
5.3.2 Machine learning enhanced fringe analysis methods 5-6
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AdvancesinOpticalFormandCoordinateMetrology
5.4 Phase unwrapping 5-6
5.4.1 Conventional phase unwrapping methods 5-7
5.4.2 Non-conventional phase unwrapping methods 5-8
5.4.3 Machine-learning-based phase unwrapping methods 5-9
5.5 High dynamic range techniques 5-9
5.6 Calibration 5-11
5.6.1 Conventional methods 5-11
5.6.2 Recent developments 5-12
5.7 High-speed FPP realisation 5-13
5.7.1 Conventional high-speed FPP methods 5-13
5.7.2 Recent developments 5-14
5.8 Towards automation 5-15
5.9 Towards integrated solutions 5-16
5.9.1 3D imaging system for crime scene evidence collection 5-17
5.9.2 Robotic path planning 5-17
5.10 Summary 5-19
References 5-19
6 Machine learning approaches 6-1
Joe Eastwood, Danny Sims-Waterhouse and Samanta Piano
6.1 Introduction 6-1
6.2 Overview of machine learning and machine learning methods 6-2
6.3 Machine learning for stereo matching 6-7
6.3.1 Learned stereo machines 6-9
6.4 Machine learning for phase unwrapping 6-10
6.5 Learning depth from a single image 6-12
6.5.1 Characterisation of cameras and projectors 6-13
6.6 Machine learning for point cloud analysis 6-14
6.6.1 Point cloud segmentation 6-15
6.6.2 Point cloud registration 6-18
6.6.3 Point cloud completion 6-20
6.7 Conclusions 6-21
References 6-21
7 Precision freeform metrology 7-1
Chi Fai Cheung, Lingbao Kong and Mingjun Ren
7.1 Overview of freeform surfaces 7-1
7.2 Framework for precision freeform metrology 7-3
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7.3 Characterisation of freeform surfaces 7-6
7.3.1 Surface fitting and reconstruction 7-6
7.3.2 Surface matching 7-10
7.3.3 Surface parameters for form error evaluation 7-14
7.4 Conclusions and future research 7-15
Acknowledgments 7-16
References 7-16
8 Performance verification for optical co-ordinate metrology 8-1
Adam Thompson and Nicholas Southon
8.1 Introduction 8-1
8.2 Material measures 8-2
8.2.1 Material measure 1 8-2
8.2.2 Material measure 2 8-3
8.2.3 Material measure 3 8-4
8.2.4 Material measure 4 8-4
8.3 The different types of performance verification test 8-5
8.4 Specification of errors 8-6
8.4.1 General guidelines for performance verification 8-7
8.5 Performance verification procedures 8-8
8.5.1 Measurements with representative points 8-9
8.5.2 General preparation for the performance verification test 8-10
8.5.3 Probing characteristics 8-11
8.5.4 Distortion characteristics 8-13
8.5.5 Length measurement errors 8-20
8.6 Compliance with specifications 8-23
8.6.1 Formal definition of performance verification 8-23
8.6.2 Retesting after a failed compliance with specifications 8-24
8.7 A final note on the validity of performance verification 8-24
References 8-25
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