介绍了一种基于晶体斜劈的偏振光法拉第旋转角的实时线性测量方法,并将该方法用于磁光薄膜温度特性的测量。相比于传统的偏振角度测量方法,晶体斜劈方法不仅不受光源功率波动影响,而且在测量过程中无需调节光学元件,可以实时测量。更重要的是用该方法可以实现任意法拉第旋转角的线性测量，偏振角度测量的相对精度可达到8.7×10-4。将该方法用于测试掺Tb离子的BiYIG磁光薄膜在不同温度下的Verdet常数,研究其温度特性。

The real-time linear measurement of the Faraday rotation angle of polarized light based on the crystal wedge is presented. Compared to the traditional methods, the measurement based on crystal wedge is not only insensitive to the light power fluctuation, but also can realize the real-time detection due to no adjustment of the optical elements during the experiments. More importantly the linear measurement can be kept for any polarization angle, and the relative accuracy reaches 8.7×10-4. The Verdet constants of the BiYIG magneto-optical film with Tb doping under various temperature are investigated by this method, and the temperature dependence is analyzed.