Design and verification of fast-rotating polarization imaging system in dynamic scenes

Abstract

In order to improve the real-time performance of the division-of-time polarization imaging system applied in dynamic scenes, the traditional rotating polarizer imaging scheme is improved and a fast-rotating polarization imaging system is designed. The scheme of the camera exposing during the uniform rotating of the polarizer is applied in the system, and the intensity images of different polarization angles are collected when a designed hollow turntable drive the polarizer to rotate rapidly. Based on the brief introduction of the principle of the polarization imaging system of fast rotating polarizer, the optical-mechanical structure design and core components of the system are introduced in detail, and the polarization imaging experiment of the system is carried out. The pipeline calculation method and the least square method are used to solve 5 adjacent intensity images of the target scene every time to calculate the degree of linear polarization (DoLP) and the angle of polarization (AoP). The test results show that the system can get polarization images at a frame rate of 80 frames per second (FPS) or with the pixels of 1280×1180. It is shown that when the imaging frame rate is 51 FPS, the polarization images obtained by solving 5 consecutive frames of intensity images have better detail recognition ability than those obtained by solving 3 consecutive frames of intensity images. Compared with the division-of-time polarization imaging system of the start-stop rotating polarizer, this division-of-time polarization imaging system with fast rotating polarizer increases the polarization imaging frame rate, improves the real-time performance, and enhances the detection ability to dynamic scenes.