Title:
ZERO OFFSET ERASING METHOD FOR OPTICAL FIBER GYRO
Document Type and Number:
Japanese Patent JPH04184116
Kind Code:
A
Abstract:
PURPOSE:To erase zero offset so as to have high quality output by having an output from a difference signal of the 1st and 2nd signals, obtained by application of modulations with reversed polarity by a stable phase modulation and the same modulation factor. CONSTITUTION:A light beam 1a from a laser light source 1 operated by a driver 1A is incident upon a sensor coil 6 after it passes through the 1st coupler 2, a polarizer 3, and the 2nd coupler 4, and modulated by a modulator 5 connected with an oscillator 11. The light beam 1a is radiated from the coil 6 and retrograded, and incidented from the coupler 2 to a detector 7 and an interference phase difference of light is detected by a signal processing circuit 8. At the circuit 8, the detected signal from the detector 7 is output as an output signal 15, through an amplifier 9, a demodulated circuit 10, a compensation circuit 13, an amplifier 14, and a subtraction circuit 22. In order to obtain gyro output 15, without zero offset, modulation with a modulating period t1 by the oscillator 11, and modulation with a period t2, by an oscillator 21, having the same modulation factor with reversed polarity, are applied to circuits 10 and 20.
Inventors:
MIMURA MICHIHIKO
Application Number:
JP30881390A
Publication Date:
July 01, 1992
Filing Date:
November 16, 1990
Export Citation:
Assignee:
TAMAGAWA SEIKI CO LTD
International Classes:
G01C19/72; (IPC1-7): G01C19/72
Attorney, Agent or Firm:
Mitsuteru Soga (3 outside)