Polarization noise and reduction technology in micro optical gyroscope

Micro optical gyroscope has advantages of integrated optoelectronic technology. Its ring resonator is fabricated by optical integrated technique. Polarization fluctuation induced noise is one of the dominant noise sources in resonator. State of polarization of the input light, polarization-maintaining quality of the coupler and the waveguide, and the temperature fluctuation are main parameters which affect polarization noise of micro optical gyro. Simulations and validation experiments were made for these factors. As a countermeasure, an improved layout for the gyroscope is put forward to reduce the polarization noise, which includes a polarizer in front of the resonator and the polarization-maintaining waveguide resonator. Polarization-maintaining waveguide and coupler were designed according to the theory of geometrical birefringence. The improved layout provides theoretical basis and guidance for further development of the micro optical gyroscope.