PROCEEDINGS ARTICLE | January 31, 2012
Proc. SPIE. 8351, Third Asia Pacific Optical Sensors Conference
KEYWORDS: Digital signal processing, Phase modulation, Modulation, Waveguides, Fiber optics, Polarization, Fiber optic gyroscopes, Signal processing, Integrated optics, Gyroscopes
The operation of Fiber Optic Gyro is based on the Sagnac Effect which states that light beams propagating
along opposite directions in a rotating frame experience an optical path length difference. These two counter-propagating
waves propagate within a closed fiber coil, and when this coil rotates the resultant phase difference is proportional to the
rotation rate Ω. Fiber optic gyroscopes are desirable devices for many navigation and guidance applications because,
being solid state devices, they have several major advantages including light weight, long working lifetimes, no moving
parts and operate using low voltage power. In this paper the Optolink's single-axis and three-axis fiber optic gyroscopes
are described. The Optolink's FOGs consist of the light-emitting diode, one or three photodetectors, circulators and
polarization maintaining fiber couplers to divide the light into two or three parts, one or three sets of ring interferometers
to sense one or three orthogonal angular rates, and installed PCB signal processing circuits. The ring interferometer
consists of a multifunction integrated optic chip and polarization maintaining fiber coil, both these components are
designed and fabricated by Optolink. The results illustrate the versatility of the technology, showing its potential to meet
both the low-cost, compact sized needs of tactical guidance, as well as the very high performance needs of inertial
navigation and precision applications. The optic and electronic blocks of closed-loop gyroscopes with integrated optic
components are also considered in this paper.
