Controlling the coupling of counterpropagating waves in a laser gyroscope with a nonplanar cavity when working with a Zeeman dither

In this paper we investigate the effect of the coupling of counterpropagating waves, caused by radiation scattering, on the characteristics of a Zeeman laser gyroscope. We present methods for measurement of this effect in a laser gyroscope when it operates with a frequency biasing. The proposed complex methods for measuring this quantity are based on the amplitude modulation of one of the waves and the phase restoration of the beat signal. The obtained values of the waves coupling magnitude were used to control piezoelectric actuators that regulate the gyroscope cavity length in order to minimize the coupling of the counterpropagating waves. The magnitude of the coupling decreased by a factor of 2–5 times. The laser gyroscope parameters were measured when it operated with the control system of the counterpropagating waves coupling.