曲率变化对激光陀螺损耗及性能的影响研究

为了研究曲率半径变化对激光陀螺性能参数的影响，基于谐振腔理论，建立了衍射损耗理论计算模型，通过仿真计算了曲率变化引起激光陀螺束腰的变化，从而导致衍射损耗的变化。从光阑处衍射损耗对陀螺背向散射的影响出发，分析了束腰对激光陀螺性能的影响。通过分析计算得出:当反射镜曲率变化小于0.3 m时，引起衍射损耗变化3%，导致零偏最大变化约0.013；当反射镜曲率变化0.6 m时，引起衍射损耗变化约15%，导致零偏最大变化约0.021；而曲率半径变化大于1.5 m时，衍射损耗变化达30%以上，这将引起谐振腔失谐即无法产生激光振荡。通过改变不同曲率，测量陀螺腔损耗和性能，所得的试验结果和理论计算一致，曲率半径变化对衍射损耗和陀螺性能影响较为显著。

Influence of curvature variation on loss and performance of ring laser gyro

In order to study the influence of different curvatures on the performance parameters of ring laser gyro (RLG), the diffractive loss calculation model was established in theory based on the cavity theory. The waist variation of RLG resulted from the curvature variation assembly was calculated by simulation, which could further cause diffraction loss variation. And starting from the effect of aperture diffractive loss on the backscattering of RLG，the influence of waist on the performance of RLG was analyzed. The calculated results indicates that the variation of diffractive loss is 3% when the variation of the curvature radius is less than 0.3 m, which would cause the bias varying 0.013 Hz; the variation of diffractive loss is 15% when the variation of the curvature radius is about 0.6 m, which would cause the bias varying 0.021 Hz; thus, the variation of diffractive exceeds to 30% when the variation of the curvature radius is more than 1.5 m, which would cause the resonator detuning, that is no laser comes into being. Both loss and bias were measured when the curvature was changed. The test results accords with the theory, the variation of curvature has obviously effect on diffractive loss and its performance.