OPTICAL FIBER GYROSCOPE HAVING WIDE DYNAMIC RANGE

摘要

PURPOSE:To make it possible to obtain stable output over a wide dynamic range, by providing a zero method servo circuit and outputting a phase difference signal corresponding to phase difference generated in a sensor coil. CONSTITUTION:An optical fiber gyroscope is constituted of a light emitting element 32, a light receiving element 36, an optical fiber 42 having parts respectively connected to a sensor coil 44 and phase modulators 46, 48 and a zero method servo circuit consisting of a substraction circuit 66, an integrating circuit 68, a voltage control oscillation circuit 70 and a wave form shaping circuit 76. By this constitution, phase difference due to rotation received by the sensor coil 44 can be determined from the control voltage of the zero method servo circuit but not from the output itself of the light receiving element 36. Therefore, corresponding to the phase difference generated in the sensor coil 44, the output of the light receiving element 36 can be outputted as a phase difference signal when the phase difference is small and the voltage of the zero method servo circuit can be outputted as the phase difference signal when the phase difference is large.