Townsend & Townsend
Optical gyro, signal processing apparatus for the same and method of driving phase modulator used in the same
 An optical gyro includes: an optical propagation path in cooperation with a rotation axis, for propagating a pair of light beams therethrough simultaneously clockwise and counterclockwise, respectively, and causing a phase difference of light based on Sagnac effect; an optical system optically coupled to the optical propagation path, for effecting a generation, a distribution or coupling, a polarization, a frequency shift and a phase modulation of light beams and transducing a light beam indicating the phase difference of light into a corresponding electric signal to output a photoelectric output signal; and a signal processing circuit operatively connected to the optical system. The signal processing circuit effects a digital demodulation for the photoelectric output signal to obtain a signal proportional to an angular velocity with respect to the rotation axis, thereby realizing a stable phase modulation and an improvement in characteristics of the optical gyro. Also, it is possible to expand a maximum range of detection of the input angular velocity. 
Mitsubishi Precision Co., Ltd.
G
G01C
inventional
Akihiro Yoshiaki Naoshi
Kurokawa Hayakawa Murayama