为解决偏振棱镜消光比参量传统检测方法中, 由于光线的非垂直入射和消光位置定位误差等因素的影响, 导致不能精确测量的问题, 以格兰-泰勒棱镜为例, 通过对偏振光进行磁光调制以精确确定待测棱镜消光位置, 并在消光位置附近多次小角度转动待测棱镜, 以减小光线的非垂直入射对出射光强产生的非线性微扰.仿真和实验验证表明, 该方法可以准确地得到消光光强与平行光强, 得出消光比参量,满足测量准确度要求.

In traditional method of testing the extinction rate of polarizing prism, as the incidence is not vertical and the position of extinction can′t be located accurately, extinction ratio can be measured accurately neither.To solve this problem, taking Glan-Taylor prism for example, magneto-optic modulation was adopted to define the extinction place accurately, rotating the prism several times to decrease the nonlinear perturbation caused by oblique incidence. Simulation and experiment show that, the minimum and maximum light intensity can be gained, the extinction rate was also obtained and fulfilled the precision requirement.