提出了一种基于光弹调制技术的波片相位延迟量测量方法,利用米勒矩阵对其进行了理论推导和误差分析。测量光路包括激光器、起偏器、光弹调制器、被测波片、检偏器和光电探测器,利用探测信号的归一化基频分量和二次谐波分量精确计算出被测波片的相位延迟量。该方法能测量紫外到红外光谱范围内任意相位延迟量的波片,误差分析表明其误差小于0.05°。实验验证了该测量方法的有效性,波片相位延迟量的重复测量精度为0.0048°。

A new method based on photoelastic modulation technology for measuring retardation of a wave plate is presented. The theoretical analysis of the measurement principle and error of this method are given by using Miller matrix. The measurement setup is composed of laser source, polarizer, photoelastic modulator, wave plate to be measured, analyzer and photodetector. The retardation of the wave plate is computed by using the normalized fundamental frequency component and the second harmonic component of the detected signals. This method can measure the retardation of wave plate with a large spectral range from ultraviolet to infrared. The error of this method is less than 0.05°. The precision of measurement repeatability is less than 0.0048°, and the feasibility of the method is verified experimentally.