Low drift and high sensitivity Fiber Optic Gyroscope using tunable VCSEL as optical source

Continuously tuned VCSEL is employed as optical source for a fiber optic gyroscope (FOG) for the first time. Results show very low drift and are comparable to those obtained by systems employing superluminescent diodes (SLD).

I. Introduction

Fiber optic gyroscope (FOG) is a gyroscope that uses the interference of light to detect mechanical rotation. The sensor element consists of a coil of optical fiber where two light beams travel along the fiber in opposite directions. As a result of the Sagnac effect, the beam traveling against the rotation experiences a shorter path than the other beam. The resulting phase shift affects how the beams interfere with each other when they are combined again. Thus, the intensity of the combined beam depends on the rotation rate of the device.