Fiber Optic Technology: Applications to Commercial, Industry, Military, and Space Optical Systems

280 Pages·2005·4.093 MB·English

by  Asu Ram Jha

Fiber Optic Technology
Applications to Commercial, Industrial,
Military, and Space Optical Systems
Asu Ram Jha, Ph.D.
www.scitechpub.com
Raleigh, NC
Copyright © 2007 by SciTech Publishing
Previously published by Noble Publishing, a division of SciTech
Publishing, Inc. All rights reserved. No part of this book may be
reproduced in any form or by any means without prior written
permission of the publisher.
SciTech Publishing, Inc.
911 Paverstone Drive, Suite B
Raleigh, NC 27615
Phone: [phone] Fax: [phone]
Email: [email protected]
Information contained in this work has been obtained from sources
believed to be reliable. However, neither SciTech Publishing nor its
authors guarantee the accuracy or completeness of any information
published herein, and neither SciTech Publishing nor its authors shall be
responsible for any errors, omissions, or damages arising out of use of
this information. This work is published with the understanding that
SciTech Publishing and its authors are supplying information but are not
attempting to render engineering or other professional services. If such
services are required the assistance of an appropriate professional
should be sought.
Printed in the United States of America.
10 9 8 7 6 5 4 3 2 1
ISBN: 1-884932-60-6
ISBN 13: 978-1-884932-60-1
Library of Congress Cataloging-in-Publication
Jha, A.R.
Fiber optic technology: applications to commercial, industrial,
military, and space optical systems/ Asu Ram Jha.
p. cm.
Includes bibliographical references.
ISBN 1-884932-60-6
1. Fiber optics—Industrial applications. 2. Optoelectronic
devices. I. Title.
TA1800.J 49 2004
621.36’92—dc22
200405083
Preface
M
aturity of fiber optic and photon technologies has opened the door for
immediate applications of fiber optic (FO)-based devices and sensors
to covert communications, long-haul communications and telecom-
munications, airborne reconnaissance, space surveillance, premises security,
metropolitan data transmission, missile warning, drone electronics, pollution
monitoring, high resolution thermal imaging, medical diagnosis, and noninvasive
surgical procedures. The FO based devices and components have critical use in
host of many systems best suited for commercial, industrial, military, and space
applications. It is important to mention that FO-based devices and components
can operate reliably under severe EMI, RFI, radiation, thermal and mechanical
environments. Such operational capability is best suited for military, space, and
industrial applications. Deployment of FO-based systems in commercial, indus-
trial, military and space systems is possible due to rapid development and avail-
ability of state-of-the art FO devices and components. Integration of emerging
technologies such as high-temperature superconductor, acousto-optic, infrared,
MEMS, and MMIC technologies in some FO-based sensors has been identified
with emphasis on cost and reliability.
This book summarized the performance capabilities of important FO compo-
nents and devices such as Erbium-doped fiber amplifiers (EFDAs), Raman
amplifier, Fiber Bragg Gratings (FBGs), optical switched, circulators/isolators,
programmable delay lines, tunable short-pulse lasers, clinical diagnostic probes,
catheters for angioplasty procedures, optical links for phased array antennas,
gyros for missiles, and high power cables best suited for ECM towed decoys,
target illumination, and remote monitoring of nuclear power plants.
The book is well organized and covers wide variety of topics and various
applications in commercial, industrial, military, and space systems requiring
cutting-edge FO, photonic, and electro-optic technologies. Mathematical expres-
sions for electric field, group delay, coupling efficiency, propagating modes, and
fractional modal power levels in core, cladding, and jacket layers, which may be
of significant importance to students who wish to expand their knowledge in the
FO technology areas. The book is written in language for easy comprehension by
x
Preface xi
students and entry level engineers and contain numerical data to demonstrate the
unique performance capabilities of FO-based components and systems widely
used in scientific and industrial research. The book has been prepared specially
for graduate students, research scientists, design engineers, clinical research,
project engineers, and product development managers who are actively involved
in the design and development of FO-based devices and sensors for specific
applications. This book will be found very useful as a reliable reference hand-
book to research scientists, project managers, research scientists, and clinical
researchers. This book will be most beneficial particularly to those who wish to
broaden their knowledge in the application of FO technology to various devices
and sensors. The author has made every attempt to provide well-organized mate-
rial using conventional nomenclature, a constant set of symbols, and identical
units for rapid comprehension. Relevant quantities, symbols, functions, and units
commonly used to describe the performance parameters of FO devices are
provided. Latest performance parameters on widely used EO devices and sensors
are provided from various reference sources with due credits to authors or organi-
zations involved. The bibliographies include significant contributing sources. The
book presents the latest design, development and research data on several FO-
based devices and systems.
This book is comprised of eight chapters. Important mathematical expres-
sions have been derived throughout the book to provide the readers the analytical
aspects of the FO-based devices or systems. Chapter one identifies the critical
elements of the optical fiber and their important characteristics. Critical perfor-
mance requirements for the core, cladding, and jacket are defined. Typical perfor-
mance parameters for the optical fiber elements as a function of temperature and
wavelength are identified with emphasis on linearity.
Chapter two derives the relevant mathematical equations for electric field,
group delay, coupling efficiency, dominant and secondary propagation modes,
and fractional modal power carried by the core, cladding, and jacket layers. Frac-
tional modal power computational results assuming appropriate values of core,
cladding, and jacket are provided. These computations indicate that roughly 90%
of the fraction modal power is in the fiber core and rest in the cladding layer. The
computations further indicate that the fraction modal power is much less than 1%
even in the best-designed jacket.
Chapter three summarizes the performance capabilities and limitations of
passive FO components and devices such as optical switches, couplers, equal-
izers, polarizers, de-polarizers, router, circulators, isolators, and fiber Bragg
grating devices. This chapter identifies benefits of these passive components and
summarizes the potential performance improvement of the FO-based sensors. In
brief, one can see significant performance improvement by deploying the passive
components with appropriate device performance characteristics.
xii Preface
Chapter four defines the performance requirements of the FO devices and
components best suited for military system applications. Such devices include
programmable delay lines; optical control links for active phase array antennas
widely used by missile defense radars, laser energy delivery cables, drone opto-
electronics, laser-based gyroscopes for missile navigation, and high-resolution
thermal imaging sensors. In addition, FO devices best suited for battlefield appli-
cations are briefly discussed with emphasis of stable and reliable performance
under severe operating conditions.
Chapter five described the performance requirements and capabilities of
widely used FO components such as EDFAs, Raman amplifiers, tunable lasers,
gain flattening filters, ripple control devices, FO-based MEMS devices, optical
modulators, dispersion compensators, and monowavelength devices. Perfor-
mance requirements of FO devices or components best suited for broadband
telecommunications and long-haul communications systems using WDM or
dense-WDM multiplexing techniques are briefly discussed. Benefits of EDFAs,
Raman amplifiers, gain flattening devices, dispersion compensators, and ripple
control devices are identified to achieve low dispersion, high data rates with low
BER capability, long communication distances, and reduced cross-talk between
the adjacent channels.
Chapter six focuses on the critical performance parameters of the FO-based
devices and components widely used by the high data rate telecommunications
equipment and long-haul communications systems using wavelength-division-
multiplexing (WDM) and dense-WDM (DWDM) techniques. Performance
parameters of FO components best suited for metropolitan LAN and WLAN
systems are briefly discusses. Performance parameter values of FO devices
widely used in broadband telecommunications equipment and long-haul commu-
nications systems are of critical importance, if maximum economy and reliable
operation are the principal system requirements.
Chapter seven discusses core and cladding material requirements for special
FO transmission lines for various scientific studies, clinical research, medical
diagnosis, and noninvasive surgical procedures. This chapter essentially defines
performance characteristics of the core, cladding, and jacket layers capable of
providing stable and reliable performance levels of the EO-based probes best
suited for arthroscopy surgery, laser angioplasty, dental diagnostic and surgical
procedures, laser-based eye surgical procedures, colon testing, epileptic treat-
ment, angiograms to examine arteries, detection of ulcers and gastronomical
diseases and elimination of blood clot associated with an ischemic stroke.
Requirements for FO short pulse lasers and low-loss, low-dispersion optical
fibers are defined, which are best suited for a variety of surgical procedures in the
fields of ophthalmology, dermatology, dentistry, angioplasty, and keratotomy. FO
cable design aspects are briefly discussed, which are very critical in carrying the
laser energy to target.
Preface xiii
Chapter eight deals with FO-based sensors widely used in various industrial
applications. Such sensors include level sensors widely deployed in the chemical
and petrochemical industries, temperature sensors to monitor frequently indus-
trial processes, displacement sensors for precision machining of the parts used in
military, space, and medical applications, pressure sensors to monitor boiler
steam/water pressure levels, intensity-modulated sensors to measure electric and
magnetic field intensities, and interferometer sensors to detect phase shift in an
optical signal. Custom-built optical connectors for industrial applications are
required to ensure reliable and stable optical performance under severe operating
environments. A cantilevered optical fiber and heat-sink chip may be required for
significant reduction in fiber breakdown leading to laser beam misalignment,
which can seriously affect the coupling efficiency. For heavy industrial applica-
tions, optical fibers that are double-sheathed in super-rugged stainless steel
square-lock with an internal PVC/Kevlar sheath are recommended to provide
high mechanical integrity under severe mechanical stresses and vibrations. In
some industrial applications, steel extruded jackets are necessary to guard against
accidental cut or bruise or bend. In addition, a Kevlar aramid strength member
may be required for added strength and isolation needed to achieve stable optical
performance from the sensors.
The responsibility for the final form of the book, including the errors or
omissions, is mine. The scope of the book, the order of presentation of the mate-
rial, and the sectional divisions within the chapters are based on good engi-
neering judgment and judicial choice. I wish to thank Dennis Ford at Noble
Publishing for his critical review of the manuscript and for his patience in accom-
modating the last-minute additions and changes to the text. Last, but not the least,
I want to thank my wife Urmila Jha, daughter Sarita Jha, son-in-law Anu Mang-
lani and daughter Vineeta Manglani, who inspired me to complete this book on
time despite participating in social engagements. Finally, I wish to express my
sincere thanks and deepest appreciation to my wife, who has been very patient
throughout the preparation of this book.
—Dr. A.R. Jha
Contents
Foreword...................................................................................ix
Preface........................................................................................x
1 Performance Requirements for
Fiber Core, Cladding, and Jacket................................................3
1.1 Materials for Various Elements of an Optical Fiber 3
1.2 Material Requirements for the Core 4
1.3 Material Requirements for Coating 9
1.4 Material Requirements for Buffer 9
1.5 Material Requirements for Jacket 11
1.6 Various Loss Mechanisms in Optical Fiber 13
1.7 Dispersion in Optical Fibers 20
1.8 Polarization Loss 25
1.9 Summary 25
1.10 References 26
2 Expressions for Electric Field, Propagating Modes,
Group Delay, and Coupling Coefficients..................................27
2.1 Electromagnetic (EM) Fields and Propagating Modes 28
2.2 Impact of Normalization Procedure 31
2.3 Impact of Cutoff Conditions on Eigenvalue Equations 32
2.4 Linearly Polarized Modes 35
2.5 Physical Significance of Parameter θ 36
p
2.6 Computations of Normalized Eigenvalues (Up)
as a Function of Normalized Frequency (V) 37
2.7 Impact of Parameter δ on the Accuracy of Eigenvalues 37
2.8 Number of Propagating Modes in Optical Fiber 38
2.9 Crosstalk Between Optical Fibers 41
2.10 Group Delay in Optical Fibers 44
2.11 Group Delay Spread 46
2.12 Modal Power Within Optical Fiber 48
2.13 Fractional Power in Core, Cladding, and Jacket Layers 50
2.14 Summary 53
2.15 References 54
v
vi Contents
3 Fiber Optic Passive Components.............................................55
3.1 Optical Limiters 55
3.2 Optical Filters 56
3.3 Optical Couplers 60
3.4 Optical Isolators and Circulators 61
3.5 Optical Switches 65
3.6 High-Speed Optical Interconnect (HSOI) Device 72
3.7 FO Bundle (FOB) 72
3.8 FO Probes 73
3.9 FO-Based Optical-Power Combiners 74
3.10 FO Tunable Dispersion Compensators 76
3.11 FO-Based Light Scopes 78
3.12 FO Strain Sensors 79
3.13 FO-Based Security Uniforms 79
3.14 FO-Based Interrogation Sensors 80
3.15 FO Lighting System 80
3.16 FO Collimators 81
3.17 FO Polarizers and Depolarizers 81
3.18 Erbium-Doped Microfiber (EDMF) Laser 82
3.19 FO Polarization Scramblers 82
3.20 Summary 85
3.21 References 85
4 Fiber Optic Components for Military and
Space Applications.....................................................................87
4.1 FO Delay Lines for ECM Equipment 87
4.2 FO-Based Michelson Array 96
4.3 Tunable Dispersion Compensation 98
4.4 Optical Ring-Resonator Gyros (ORRGs) 103
4.5 All-Fiber, Q-Switched (AFQS) Laser 107
4.6 Solid-State Beacon Laser Illuminator (SSBLI) 109
4.7 FO Ring Laser (FORL) Gyros 112
4.8 Infrared Countermeasures (IRCM) Systems 113
4.9 Three-Dimensional Laser Tracking (3-DLT) Systems 114
4.10 Optical Control of Transmit/Receive (T/R)
Modules in Phased Array Radars 115
4.11 Summary 120
4.12 References 121
Contents vii
5 Integration of Fiber Optic Technology in Commercial and
Industrial Systems....................................................................123
5.1 Optical Sensor Using Cryogenic and FO Technologies 123
5.2 All-Optical Nonlinear (AON) Switch 126
5.3 Optical System for Tracking High-Speed Train Tracks 132
5.4 FO Gyroscope (FOG) for Aerospace Applications 133
5.5 FO Voltage Sensor (FOVS) 138
5.6 FO CATV Receiver 141
5.7 Optical Sensors for Detection of Poisonous Gases
and Chemical Agents 143
5.8 FO Sensor for Quality Control and Assurance 146
5.9 FO Imaging Probes to Study Rock Structures 149
5.10 FO Sensors for Site Monitoring 150
5.11 Summary 154
5.12 References 154
6 Fiber Optic-Based Communications and
Telecommunications Systems................................................156
6.1 FO Communication Links 157
6.2 Optical Communications and Telecommunications Systems 162
6.3 Performance Requirements for WDM Systems 168
6.4 Capabilities of Metropolitan WDM Systems 175
6.5 Multiplexing and Demultiplexing Techniques 177
6.6 Optical Transceivers 182
6.7 Optical Amplifiers for Communications Systems 184
6.8 Summary 198
6.9 References 199
7 Fiber Optics for Medical and Scientific Applications...........200
7.1 Potential Techniques for DNA Analysis 201
7.2 Laser and FO Technologies for Dental Treatment 204
7.3 Spectroscopic Technology for Life-Science Research 208
7.4 Near-IR Spectroscopic Technique for Epilepsy Treatment 211
7.5 Application of Laser and FO Technologies
to Photodynamic Therapy (PDT) 212
7.6 Optical Tomography Using FO Technology
for Medical Treatments 214
7.7 Endoscopic Sensor Using FO and Laser Technologies 216
viii Contents
7.8 FO-Based Procedures for Treating Heart Diseases 217
7.9 Vision Correction Using Laser Surgical Procedure
and FO Technology 219
7.10 Laser Technology for OT Applications 221
7.11 Q-Switched Laser for Clearing a Cerebral Artery Obstruction 221
7.12 Laser-Based Flow Cytometry 222
7.13 Laser-Based Endoscopic Technology for Colon Imaging 223
7.14 Fiber-Based Delivery Systems for Medical Applications 225
7.15 Summary 227
7.16 References 227
8 Fiber Optic Sensors for Various
Industrial Applications.............................................................229
8.1 FO Level Sensors 230
8.2 FO-Based Displacement Sensors 236
8.3 FO-Based Flow Sensors 240
8.4 FO Techniques for Chemical Analysis 243
8.5 FO Sensors for Temperature Monitoring 246
8.6 FO Pressure Sensors 248
8.7 FO-Based Magnetic- and Electric-Field Sensors 251
8.8 Summary 254
8.9 References 254
Index.......................................................................................257