Differential fiber-optic gyroscope for rotational seismic observation

A differential fiber optic gyroscope (FOG) driven by two broadband light sources with different wavelengths was demonstrated theoretically and experimentally, and bias drift and angle random walk both can be reduced considerably due to common-mode error cancellation. A 3-component fiber optic rotational seismometer based on the differential FOG was developed and successfully applied in rotational seismic observation.