Optical Fiber Sensor Technology

511 Pages·1995·10.563 MB·English

by  D. A. Jackson (auth.), K. T. V. Grattan, B. T. Meggitt (eds.)

OPTICAL FIBER
SENSOR TECHNOLOGY
Optical and Quantum Electronics Series
Series editors
Professor G. Parry; University of Oxford, UK
Professor R. Baets) University of GentJBelgium
This series focuses on the technology, physics and applications of optoelectronic
systems and devices. Volumes are aimed at both research and development staff
and engineers involved in the application of optical technologies. Graduate
textbooks are included, giving tutorial introductions to the many exciting areas
of optoelectronics. Both conventional books and electronic products will be
published, to provide information in the most appropriate and useful form for
users.
1 Optical Fiber Sensor Technology
Edited by K.T.V. Grattan and B.T. Meggitt
2 Vision Assistant Software
A practical introduction to image processing and pattern classifiers
c.R. Allen and N.C. Yung
Optical Fiber
Sensor Technology
Edited by
K. T. V. Grattan
Head, Department of Electrical,
Electronic and Information Engineering
City University
London, UK
and
B. T. Meggitt
ERA Technology Limited
Leatherhead, UK
SPRINGER-SCIENCE+BUSINESS MEDIA, B.V
First edition 1995
© 1995 Springer Science+Business Media Dordrecht
Originally published by Chapman & Hall in 1995
Softcover reprint of the hardcover 1st edition 1995
ISBN 978-94-010-4530-8 ISBN 978-94-011-1210-9 (eBook)
DOl 10.1007/978-94-011-1210-9
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The publisher makes no representation, express or implied, with regard to
the accuracy of the information contained in this book and cannot accept any
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A catalogue record for this book is available from the British Library
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ANSI/NISO Z39.48-1992 (Permanence of Paper).
Contents
List of contributors xv
Preface xvii
1 Overview of fiber sensor developments 1
D. A. Jackson
1.1 Introduction 1
1.2 Current state of the art 5
1.2.1 External sensors 5
1.2.2 Intrinsic sensors 5
1.2.3 Extrinsic sensors 7
1.3 Future developments 8
1.4 Summary 9
References 9
2. Foundations of optical fiber technology 11
V. Handerek
2.1 Introduction 11
2.2 Optical guidance 11
2.2.1 Modes in dielectric waveguides 14
2.2.2 Propagation in optical fibers 16
2.2.3 Single mode fibers 18
2.3 Fiber dispersion 20
2.3.1 Intermode dispersion 21
2.3.2 Dispersion in single mode fibers 23
2.4 Commercially available optical fibers 26
2.5 Fiber fabrication and strength 26
2.6 Fiber attenuation 28
2.6.1 Intrinsic attenuation factors 28
2.6.2 Extrinsic attenuation factors 30
2.7 Modal noise 32
2.8 Power handling 32
2.9 Fiber handling 33
2.9.1 Endface preparation 33
2.9.2 Interfacing sources and detectors 33
2.9.3 Fiber joints 35
vi CONTENTS
2.10 Polarization behavior in optical fibers 37
2.10.1 Polarization in nominally isotropic single
mode fibers 37
2.10.2 Polarization-controlled fibers 40
2.11 Fiber components 42
References 43
Further Reading 44
3. Sources for optical fiber sensors 45
K. T. V. Grattan
3.1 Introduction 45
3.2 Basics of radiation sources 46
3.3 Incoherent sources 48
3.3.1 Thermal sources 48
3.3.2 Discharge lamps 51
3.3.3 Solid state incoherent sources - the light-
emitting diode 53
3.4 Coherent sources 54
3.4.1 Laser operation 55
3.4.2 Laser modes and laser spectra 58
3.4.3 Laser sources applied to optical sensors 59
3.5 Choice of photon detectors 70
3.6 Summary of laser sources 70
3.7 Conclusions 72
References 72
4 Optical detectors and receivers 75
J. D. C. Jones
4.1 Introduction 75
4.1.1 The function of detectors and receivers in
optical sensors 75
4.1.2 Requirements for detectors 75
4.1.3 Classification of detectors 76
4.1.4 Overview 77
4.2 Photothermal detectors 77
4.2.1 Introduction 77
4.2.2 Thermoelectric detectors 77
4.2.3 Thermoresistive detectors 78
4.2.4 Golay cells 78
4.2.5 Pyroelectric detectors 79
4.3 Photoemissive devices 79
4.3.1 Basic principles 79
4.3.2 Photocathodes 79
4.3.3 Vacuum photodiodes 80
4.3.4 Photomultipliers 80
CONTENTS vii
4.3.5 Image intensifiers 80
4.4 Photoconductive detectors 81
4.4.1 Introduction 81
4.4.2 Performance 82
4.4.3 Materials 82
4.5 Photodiodes 83
4.5.1 Operation of junction detectors 83
4.5.2 Responsivity 84
4.5.3 Wavelength range of operation 85
4.5.4 Modes of operation 85
4.5.5 Depletion layer width and junction
capacitance 86
4.5.6 Speed of response 86
4.5.7 Avalanche multiplication 87
4.5.8 Materials 91
4.5.9 Device structures 91
4.6 Receivers 94
4.6.1 Front end designs 94
4.6.2 PET preamplifiers 96
4.7 Noise in photodiode receivers 96
4.7.1 Summary of noise sources 96
4.7.2 Dark current and shot noise 97
4.7.3 Thermal and amplifier noise 98
4.7.4 Signal-to-noise ratio 98
4.8 Conclusions 100
References 101
Further reading 103
5. Multimode optical fiber sensors 105
G. R. Jones, R. E. Jones and R. Jones
5.1 Introduction 105
5.2 Formal systems approach 106
5.2.1 Performance criteria 106
5.2.2 Formal representation of a fiber system 108
5.3 Source and fiber effects 111
5.3.1 Spectral emission of source (P(A.» 111
5.3.2 Wavelength-dependent fiber attenuation (F(A.» 112
5.3.3 Fiber modal effects 113
5.4 Some important modulation mechanisms 115
5.4.1 Extrinsic transmission-reflection modulation 116
5.4.2 Quasi-intrinsic modulation 120
5.4.3 Wavelength selective modulation 125
5.5 Signal processing and system architecture 132
5.5.1 Analog techniques 133
5.5.2 Broadband interferometric techniques 140
viii CONTENTS
5.5.3 Digital and time domain techniques 153
5.5.4 Full hybrid techniques 157
5.6 Conclusions 159
References 159
6 Multimode optical fiber chemical sensors 161
J. O. W. Norris
6.1 Introduction 161
6.2 Perceived advantages and disadvantages for chemical
sensing 162
6.2.1 Advantages 162
6.2.2 Disadvantages 163
6.3 Underlying principles of fiber optic chemical
sensors 164
6.3.1 Optical effects 164
6.3.2 Chemical equilibria 169
6.4 Classifying fiber optic sensors for chemical sensing 171
6.5 Description of some illustrative sensors 172
6.5.1 Extrinsic species 172
6.5.2 Intrinsic species-specific sensors 184
6.5.3 Nonspecies-specific techniques 189
6.5.4 Indirect techniques 191
6.6 Conclusions 193
References 193
7 Single mode optical fiber sensors 197
V. Handerek
7.1 Introduction 197
7.2 Interferometer configurations 198
7.2.1 Two-beam interferometers 198
7.2.2 Multiple beam interferometers 199
7.3 Transfer functions of interferometers 201
7.3.1 Two-beam interferometers 201
7.3.2 Fabry-Perot interferometer 202
7.3.3 Ring Resonator 205
7.3.4 Grating reflector 206
7.4 Signal processing techniques 207
7.4.1 Active homodyne methods 207
7.4.2 Passive homodyne methods 209
7.4.3 Heterodyne methods 211
7.4.4 Synthetic heterodyne detection 212
7.4.5 Pseudo-heterodyne detection 213
7.4.6 Range enhancement techniques 215
7.5 Fiber interactions 217
CONTENTS ix
7.6 Applications 218
7.6.1 Fiber interferometer gyroscope 218
7.6.2 Hydrophones 220
7.6.3 Particle sizing 220
References 221
8 Optical fiber modulation techniques for single mode fiber sensors 223
R. P. Tatam
8.1 Introduction 223
8.2 Optical fiber phase modulators 224
8.2.1 Phase modulators 224
8.2.2. Polarization state modulators 229
8.3 Optical fiber frequency shifters 239
8.3.1 Basic principles 239
8.3.2 Extrinsic devices 242
8.3.3 Intrinsic devices - stimulated Brillouin scattering
(SBS) 250
8.4 In-line fiber intensity modulators 257
8.4.1 Acousto-optic devices 258
8.4.2 Active overlay devices 259
References 261
9. Fiber optic white-light interferometric sensors 269
B. T. Meggitt
9.1 Introduction 269
9.1.1 Source characteristics 270
9.1.2 Basic interferometry 271
9.2 Spectral domain processing 272
9.3 Phase domain processing 276
9.3.1 Operating characteristics 276
9.3.2 Wavelength stability 278
9.3.3 Fringe order ambiguity 279
9.3.4 Temporal fringe processing 279
9.4 Spatial domain processing 287
9.4.1 Electronically scanned technique 287
9.4.2 Fringe visibility 288
9.4.3 Central fringe identification 292
9.4.4 Methods of extending the dynamic range 297
9.5 Spatial to temporal fringe generation 302
9.5.1 Operating characteristics 302
9.5.2 Dynamic operation 303
9.6 Quasi-distributed sensor systems: multiplexing 305
9.7 Bragg-grating devices 307
References 310
x CONTENTS
10 Nonlinear effects in optical fibers 313
A. J. Rogers
10.1 Introduction 313
10.2 Parametric effects 315
10.2.1 General 315
10.2.2 Phase matching 315
10.2.3 Four-photon mixing 317
10.2.4 Intensity-dependent refractive index 318
10.2.5 Optical Kerr effect 319
10.2.6 Self-phase modulation (SPM) 322
10.2.7 Solitons 326
10.2.8 Photosensitivity 328
10.3 Inelastic scattering 331
10.3.1 Spontaneous scattering 331
10.3.2 Stimulated scattering 333
10.3.3 Raman processes 333
10.3.4 Brillouin processes 339
10.4 Conclusions 344
References 344
11 Distributed fiber optic sensors 347
A. H. Hartog
11.1 Introduction 347
11.2 Classification of distributed optical fiber sensors 349
11.3 Principles of operation 350
11.3.1 Optical time-domain reflectometry 350
11.3.2 Modulation of fiber loss 351
11.3.3 Polarization effects 352
11.3.4 Numerical aperture effects 353
11.3.5 Modulation of scattering loss 354
11.3.6 Inelastic scattering 357
11.3.7 Fluorescence 360
11.3.8 Nonlinear optical effects 360
11.3.9 Discrete signal sources - quasi-distributed
sensors 362
11.3.10 Forward scattering methods 363
11.4 Performance of distributed sensors and engineering aspects 364
11.4.1 Performance criteria in distributed sensors 364
11.4.2 Constraints in the engineering of distributed
sensors 365
11.4.3 Alternative methods of interrogation and signal
acquisition 367
11.5 Applications 371
11.5.1 Power supply industry 371
11.5.2 Petrochemicals 373