相位延迟量是偏振光学元件的一个重要指标，为了精准快速地测量偏振元件的相位延迟量，提出一种具有相位补偿的级联调制的偏振元件相位延迟量检测方法。该方法采用弹光调制器（PEM）和电光调制器（EOM）作为相位延迟量检测系统的级联调制元件，利用Soleil-Barbinet相位补偿器对样品进行光学补偿。基于数字锁相技术与现场可编程逻辑门阵列（FPGA）的片上可编程系统，检测光强极值点对应的Soleil-Barbinet相位补偿器的相位参数并进行数据处理，实现样品的相位延迟量检测。实验表明，利用该方法测量样品的相位延迟量的最大相对误差为0.857%，测量精度为99.143%，验证了将偏振调制法和补偿法相结合测量相位延迟量具有较高的精度，且降低了补偿器本身对测量误差的影响。

Phase retardation is an important indicator of polarizing optical elements. To measure the phase retardation of the polarizing element accurately and quickly, a method with phase compensation and cascade modulation for detecting the phase retardation of the polarizing elements is proposed. In this method, a photo-elastic modulator (PEM) and an electro-optical modulator (EOM) are used as the cascade modulation element of the phase delay detection system, and a Soleil-Babinet phase compensator is used to compensate phase retardation for the sample. Using digital phase lock technology and a field-programmable gate array (FPGA)-based on-chip programmable system, it detects the phase parameters of the Soleil-Babinet phase compensator corresponding to the extreme point of light intensity and performs data processing to realize the detection of the phase retardation of the sample. Experiments show that the maximum relative error of using this method to measure the phase delay of a sample is 0.857% and the measurement accuracy is 99.143%, which verifies that the combination of the polarization modulation and compensation methods to measure the phase retardation has high accuracy, and the influence of the compensator itself on the measurement error is reduced.