基于微光像增强器的偏振成像系统设计与实验

为验证用微光像增强器实现偏振成像的可行性，根据偏振成像原理，设计了基于分时型偏振成像技术的微光偏振检偏器。选用三代像增强器和高动态范围数字CCD，设计了相应大口径成像物镜和中继光学耦合透镜，获得了高透过率、高调制函数（MTF）的图像耦合性能。采用数字CCD、数字图像采集卡，编写了相应图像处理软件，实现了实验室和野外微光条件下的人造目标和自然景物的偏振探测成像。结果表明，原始图像中目标与背景对比度之比为1.35，基于微光像增强器的偏振成像系统的目标与背景对比度之比为2.35，微光偏振成像能够提高夜间环境下人造目标和自然背景的对比度。

Design and experiment for polarization imaging system of low-light-level image intensifier

In order to validate the feasibility that low-light-level(LLL) image intensifier achieves polarization imaging，according to polarization imaging theory, the LLL polarization imaging system was designed based on time-sharing polarization imaging technology. A 3rd generation image intensifier and a high dynamic range charge coupled device (CCD) were selected, a big dimension aperture objective lens and a relay lens were designed. The high transmissivity and high modulated transfer function (MTF) were achieved on image coupling. A digital CCD and a digital frame capture circuit with an embedded image process module were used. The correlative software about the image process was accomplished, so that the polarization imaging experiment was accomplished for the human target and the natural background in lab and field. The test results show that the contrast of the human target to natural background is 1.35 by the conventional imaging way, and is 2.35 by the polarization imaging system of LLL image intensifier, the contrast of the human target to the natural background is improved by LLL polarization imaging technology at night.