1 A Potpourri of Comments about the Fiber Optic Gyro for Its Fortieth Anniversary: How Fascinating It Was and Still Is! 1.1 Introduction 1.2 Historical Context of the Sagnac-Laue Effect 1.3 Fascinating Serendipity of the Fiber Optic Gyro 1.3.1 The proper frequency 1.3.2 Perfection of the digital phase ramp 1.

3.3 The optical Kerr effect 1.3.4 Technological serendipity: erbium ASE fiber source and proton-exchanged LiNbO3 integrated-optic circuit 1.4 Potpourri of Comments 1.4.1 OCDP using an OSA 1.4.

2 Strain-induced ""T dot"" Shupe effect 1.4.3 Transverse magneto-optic effect 1.4.4 RIN compensation 1.4.5 Fundamental mode of an integrated-optic waveguide 1.4.

6 Limit of the rejection of stray light in a proton-exchanged LiNbO3 circuit with absorbing grooves 1.5 Conclusion Acknowledgment References 2 The Early History of the Closed-Loop Fiber Optic Gyro and Derivative Sensors at McDonnell Douglas, Blue Road Research, and Columbia Gorge Research 2.1 Introduction 2.2 Invention and Demonstration of the Closed-Loop Fiber Gyro 2.3 Looking for Error Sources, Finding New Sensors 2.4 A Flow of Ideas 2.5 Moving into Viable Products and Applications 2.6 Summary and Conclusions Acknowledgments References 3 20 Years of KVH Fiber Optic Gyro Technology: The Evolution from Large, Low-Performance FOGs to Compact, Precise FOGs and FOG-Based Inertial Systems 3.

1 Introduction 3.2 Superior Performance through End-to-End Manufacturing 3.2.1 At the heart of the FOG: creating the fiber 3.2.2 The core design of KVH open-loop FOGs 3.2.3 Design advantages 3.

2.4 Key gyro performance factors 3.3 Evolution of the Technology 3.3.1 The creation of D-shaped, elliptical-core fiber 3.3.2 The first generation of KVH FOGs 3.3.

3 The shift to digital signal processing 3.3.4 Changing the game: the invention of ThinFiber 3.3.5 Expanding capabilities with high-performance fully integrated systems 3.4 Setting the Course for the Future of FOG Technology and Expanded Applications 3.4.1 Navigation and control 3.

4.2 Positioning and imaging 3.4.3 Stabilization and orientation 3.4.4 Looking ahead 4 Fiber Optic Gyro Development at Honeywell 4.1 Introduction 4.2 IFOG Status 4.

2.1 Navigation-plus-grade IFOGs 4.2.2 Strategic-grade IFOGs 4.2.3 Reference-grade IFOGs 4.3 RFOG Development 4.3.

1 New RFOG architecture 4.3.2 RFOG experimental results 4.3.3 RFOG component development and future implementation 4.4 Summary References 5 Fiber Optic Gyros from Research to Production 5.1 Abstract 5.2 Research 5.

3 Development 5.4 Productionization 5.5 Summary References 6 Technological Advancements at Al Cielo Inertial Solutions 6.1 Introduction 6.2 Standard Control Loop 6.2.1 Control model 6.2.

2 Sub-specifications and verifications 6.2.3 Navigation accuracy sub-specification 6.2.4 Monte Carlo simulation 6.2.5 HITL simulation 6.3 Optimized Control Loop 6.

3.1 Control block 6.3.2 Monte Carlo simulation 6.3.3 HITL results 6.4 Inertial Measurements 6.5 Conclusion Acknowledgement References 7 Current Status of Fiber Optic Gyro Efforts for Space Applications in Japan 7.

1 Current Status of FOGs for Space Applications 7.2 Activities for Improving Coil Performance 7.2.1 Symmetrical winding 7.2.2 Thermal conductivity and strain attenuation 7.2.3 Zero-sensitivity winding design 7.

2.4 Summary of activity results 7.3 Conclusion Acknowledgement References 8 Fiber Optic Gyro Development at Fibernetics 8.1 Introduction and Past Development 8.2 Current Development 8.3 Basic FOG Design 8.4 Dual-Ramp Phase Modulation 8.4.

1 Low-frequency approach 8.4.2 High-frequency approach 8.5 Three-Axis Source-Sharing Design 8.6 Future Development 8.6.1 Multicore fiber 8.7 Summary References 9 Recent Developments in Laser-Driven and Hollow-Core Fiber Optic Gyroscopes 9.

1 Introduction 9.2 Backscattering Errors in a Laser-Driven FOG 9.3 Polarization-Coupling Errors in a Laser-Driven FOG 9.4 Kerr-Induced Drift in a Laser-Driven FOG 9.5 Techniques for Broadening the Laser Linewidth 9.5.1 Linewidth broadening through optimization of the laser drive current 9.5.

2 Linewidth broadening through external phase modulation 9.5.2.1 Principle and advantages 9.5.2.2 Linewidth broadening using sinusoidal modulation 9.5.

2.3 Linewidth broadening using pseudo-random bit sequence modulation 9.5.2.4 Linewidth broadening using a Gaussian white noise modulation 9.5.3 Measured dependence of noise and drift on laser linewidth 9.6 Hollow-Core Fiber Optic Gyroscope 9.

6.1 Kerr-induced drift 9.6.2 Shupe effect 9.6.3 Faraday-induced drift 9.6.4 Noise and drift performance of HCF FOGs 9.

7 Conclusions References 10 Optical Fibers for Fiber Optic Gyroscopes 10.1 Introduction 10.2 Coil Fibers 10.2.1 Stress- and form-birefringent fiber types 10.2.1.1 Elliptical-core form-birefringent fiber 10.

2.1.2 Bow-tie fibers 10.2.1.3 PANDA fiber 10.2.1.

4 Elliptical-jacket fiber 10.2.1.5 Elliptical-core, form-birefringent fiber 10.2.2 Microstructures in hollow-core, photonic bandgap fibers 10.2.2.

1 Bandgap fiber fabrication 10.2.3 Multicore fiber 10.2.3.1 Fabrication 10.3 Coil Fiber Design Considerations 10.3.

1 Diameter 10.3.2 Wavelength 10.3.3 Attenuation 10.3.4 Polarized versus depolarized design 10.3.

5 Birefringence 10.3.6 Numerical aperture 10.3.7 Coating package design 10.3.8 Radiation tolerance 10.4 Component Fibers 10.

4.1 ASE sources 10.4.2 PM splitters and couplers 10.4.3 Polarizing fibers 10.5 Epilogue References 11 Techniques to Ensure High-Quality Fiber Optic Gyro Coil Production 11.1 Introduction 11.

2 Static Performance Parameters and Testing Methods 11.2.1 Polarization-maintaining fiber coils 11.2.1.1 Insertion loss and polarization extinction ratio 11.2.1.

2 Distributed polarization crosstalk analyzer 11.2.2 Basics of polarization crosstalk in PM fibers 11.2.2.1 Classification of polarization crosstalk by causes 11.2.2.

2 Classification of polarization crosstalk by measurement results 11.2.3 Characterization of potting adhesive with a DPXA 11.2.4 Characterization of coil quality by polarization crosstalk analysis 11.2.5 Polarization-maintaining fiber characterization and screening 11.2.

5.1 Measurement fixture 11.2.5.2 Group birefringence and group-birefringence-uniformity measurements 11.2.5.3 Group birefringence dispersion measurement 11.

2.5.4 Group birefringence thermal coefficient measurement 11.2.5.5 PER measurement 11.2.5.

6 PM fiber-quality evaluation 11.2.6 Single-mode fiber coil inspection 11.2.6.1 Lumped PMD and PDL measurements 11.2.6.

2 Distributed transversal stress measurement 11.2.6.3 Degree-of-polarization tests 11.3 Coil Transient Parameter Characterization 11.4 Tomographic (3D) Inspection of Fiber Gyro Coils Acknowledgement References 12 A Personal History of the Fiber Optic Gyro References Appendix: Additional Fiber Rotation Sensor Books, Papers, and Patents A.1 Fiber Optic Rotation Sensor Contents in Books and Paper Collections References A.2 Accessing the Fiber Optic Rotation Sensor Patent Literature References.