Based on the rotation vector method, this paper combines the coupling rule and the image rotation property of the eigenmode in nonplanar ring resonator to derive expression for the lock region threshold caused by the backscattering light in a nonplanar ring laser resonator and investigate the influence of nonplanar cavity structural parameters on backscattering light and its impact on the lock region threshold. Under the condition that the lock region of left-hand and right-hand components changes synchronously, the objective of reducing and eliminating the lock region is achieved by adjusting the nonplanar cavity folding angle α of the different plane cavity. The results obtained in this paper demonstrate the convenience and accuracy of using the rotation vector method to analyze the threshold of backscattering light on the locked area of nonplanar laser gyro.
Li et al. (Sun,) studied this question.