一种偏振成像实验系统的设计

Design and Realization of Polarization Imaging Experimental System

为搭建实验系统,将3片线偏振片安装在FW102C型电动可旋转滤光轮上,通过计算机控制滤光轮转动分时采集3个不同偏振角度下的图像,再通过后续计算从而获得所观察场景的线偏振度图像和偏振角图像。针对系统误差校正,首先以马吕斯定律为基础,通过拟合方法完成偏振片偏振角度定标;然后通过手动选择配准点并借助Matlab图像处理工具箱完成视场非一致性校正。实验结果表明,所设计的偏振成像系统能够反映场景中不同目标的偏振特性。该系统结构简单、操作简便,可以满足教学实验的要求。

Active or passive polarization imaging is newly introduced in the course of photoelectric detection, which means the relevant experiment is needed to be built. In order to building the experimental system, three pieces of polarizers are installed into the FW102C motorized filter wheel. And the images under different polarization angles can be acquired through rolling of the wheel, which belongs to time-division strategy. The images of degree of linear polarization （DOLP） and angle of polarization （AOP） of the surveyed scene can then be obtained. Aiming at to calibrate the errors in the system, the polarization directions of three polarizers are calibrated firstly through curve fitting method based on Malus’s law. The nonuniformity of the three fields of view are calibrated secondly through image registration method. The results showed the designed polarization imaging system can reveal the polarized diversity of different targets in the scene. The system has the superiority of simple structure and easy operation, and can meet the need for experiment of the course.