公开(公告)号：JPH10300479A

公开(公告)日：1998-11-13

申请号：JP11166897

申请日：1997-04-30

Applicant: LITTON SYSTEMS INC

Inventor： MARK JOHN G ,  DANIEL A TAZARUTES ,  CORDOVA AMADO

IPC: G01C19/72

Abstract: PROBLEM TO BE SOLVED: To solve the problem of bias by electronic cross coupling by applying the sequence of an artificial phase shift within a specified range of an interferometer to optical beams propagated in the opposite directions, and driving a modulator for making the duration of each phase shift equal to the passing time of a sensor coil. SOLUTION: In the area of overmodulation between optical beams propagated in the opposite directions within the sensor coil of a Sagnac interferometer, a sequence of artificial phase shift is applied. The sequence is formed of phase shifts of ±aπ/2b and ±(4b-a)π/2b (wherein (a) is an odd integer, and (b) is an integer larger than 1). The waveform for driving a phase modulator is introduced from 2π radian so that the values of adjacent drive signals are differed by a π/2b or -(4b-a)π/2b in a first angle direction, and differed by -aπ/2b or (4b-a)π/2b in an angle direction opposite thereto.