Patent ID: 6643023
Filing Date: 2003-11-04
Classification: G01C

Abstract:
A method of reducing the polarization fluctuation inducing drift in a resonator fiber optic gyro, comprising the step of:setting &Dgr;L so that the relationship of &Dgr;L and &Dgr;&bgr; satisfies a formula &Dgr;&bgr;&Dgr;L=&pgr;+2n&pgr; [radian] (n: integer), or approximately satisfies the formula to minimize the error induced by the polarization fluctuation where &Dgr;L is the difference in length between L1 and L2 of two portions of a waveguide divided by a coupler and the polarization-rotating point, and &Dgr;&bgr; is the difference in propagation constant of two axes of polarization of the waveguide in a method of measuring the non-reciprocal effect such as the rotation in a reflector ring resonator comprising a sensing loop formed of the waveguide having two axes of polarization to propagate the light wave, and the coupler which is inserted in said sensing loop, guides the light wave from a laser beam source to said sensing loop and emits the light wave in said sensing loop, and having a polarization-rotating point in said sensing loop.