Division of time polarimeter (DoTP) is one of the popular imaging instruments in several applications because of its simple configuration and accurate performance. However, calibration of the optical axis of the used polarizer is also the premise of an accurate polarimeter. In this paper, a novel on-line and accurate method is proposed to calibrate the transmission angle of the polarizer using a Wollaston prism. The Wollaston prism splits the incident light into two light beams with orthogonal polarization directions, which are vertical and parallel with the beams plane, respectively. Then these two beams pass through the candidate polarizer. The detected light intensity can be adjusted by rotating the polarizer, whose position is marked by a digital encoder. The angle of optical axis of the polarizer relative to the line of points of two light beams can be solved by a series of light intensities. Finally, the optical axis of the polarizer is calibrated on-line, and the state of polarization of incident light can be measured accurately. Numerical simulation and experiments have validated the feasibility of the proposed on-line calibration method. The experimental results show that the calibration accuracy is about 0.0106° with a maximum polarization measurement error of 3.7 × 10^–4. In general, the proposed calibration method is very fast, on-line, accurate, and would be a good reference for polarization imaging and polarization calibration.

时分旋光仪 (DoTP) 因其简单的配置和准确的性能而成为多种应用中流行的成像仪器之一。然而，对所使用的偏光片的光轴进行校准也是偏振计准确的前提。本文提出了一种使用沃拉斯顿棱镜在线准确校准偏振器透射角的新颖方法。沃拉斯顿棱镜将入射光分成两束偏振方向正交的光束，分别与光束平面垂直和平行。然后这两束光束穿过候选偏振器。可以通过旋转偏振器来调节检测到的光强度，其位置由数字编码器标记。偏振器的光轴相对于两束光束的点线的角度可以通过一系列光强来求解。最后对偏光片的光轴进行在线校准，可以准确测量入射光的偏振状态。数值模拟和实验验证了所提出的在线标定方法的可行性。实验结果表明，定标精度约为0.0106°，偏振测量最大误差为3.7×10 ^–4。总的来说，所提出的校准方法非常快速、在线、准确，对于偏振成像和偏振校准有很好的参考作用。