Fiber optic gyro with reduced readout reflection coupling characteristics

摘要

A FOG design is disclosed that eliminates the need for spatially averaging the output of a readout optical fiber by using a short coherence length light source and decorrelating the orthogonal fiber modes in the birefringent readout optical fiber prior to them being received by the photodetector. The orientation of the optical output of the readout optical fiber with respect to the photodetector is at an angle other than normal incidence, which is designed to reduce the reflections from the photodetector back into the readout optical fiber. The coherence length of the source and the length and birefringence of the readout optical fiber are selected so that there is a complete decorrelation of the polarization states of the light as they pass through the readout optical fiber.