提出了一种基于基频分量消光的波片快轴标定方法,并利用琼斯矩阵对其标定原理进行了分析。激光器、起偏器、相位调制器、待标定1/4波片、检偏器和光电探测器构成标定光路,起偏器、检偏器的透光轴与相位调制器的振动轴分别成+45°和0°夹角。准直激光束依次经过起偏器、相位调制器、待标定1/4波片和检偏器,由光电探测器接收。理论分析表明该标定方法标定精度主要取决于检偏器的定位误差。实验验证了该标定方法的有效性,1/4波片快轴标定结果的最大偏差为0.043°,标准差为0.012°,标定精度为0.05°。

A method to calibrate the fast axis of a quarter-wave plate by nulling the foundamental component was proposed and the calibration principle was analyzed. The optical calibration system is composed of a laser, a polarizer, the quarter-wave plate to be calibrated, a phase modulator, an analyzer and an opto-electronic detector. The azimuths of the transmission axes of the polarizer and the analyzer with respect to the major oscillation direction of the phase modulator are +45° and 0°, respectively. A collimated laser beam passes through the polarizer, the phase modulator, the quarter-wave plate and the analyzer in turn, and then is detected by the opto-electronic detector. The theoretical analyse shows that the calibration precision depends on the azimuth error of the analyzer. The feasibility of the method was verified by experiments. The maximum deviation of the calibrated fast axis azimuth of the quarter-wave plate is 0.043°, the root-mean-square error is 0.012°, and the calibration precision is 0.05°.