一种减少空间调制快拍成像测偏仪伪信息的方法
A metho d of reducing false signature in spatially-mo dulated snapshot imaging p olarimeter
摘要
Abstract
Spatially-modulated snapshot imaging polarimeter can encode four Stokes parameters (S0, S1, S2 and S3) into a single interferogram and allow the instantaneous measurement of polarization from a single snapshot. However, the reconstructed polarization information contains aliasing signal, and the reconstructed intensity images suffer low spatial resolution because of the crosstalk between high frequency components of the image and frequency domain filtering for the polarization channels. In this paper, we propose an image superposition and subtraction method to mitigate the aliasing problem and to recover the image resolution. The two interferograms acquired from two snapshot measurements are superposed to obtain the intensity image (S0 component) of an object without the polarization components because the phases of the polarization components in the two interferograms are opposite. In comparison with the intensity of each of the original interferograms, the intensity of S0 component increases twice and its spatial resolution improves up to a maximum value offered by the instrument. Then a subtraction between the two interferograms is performed to derive the pure interference fringes while the intensity image vanishes. The intensity of the pure interference fringes also increases twice compared with that of each original interferogram because phases of the interference terms in original interferograms are opposite. The polarization images (S1, S2 and S3 components) can be reconstructed from the pure interference fringes, and do not include crosstalk signals between the high frequency components of the intensity image. The theoretical basis of the method is presented through a detailed analysis. Its feasibility is verified by both computer simulation and experiment. The simulation results show that the otherness and the structural similarity index between the input and reconstructed intensity images is zero and 1, respectively, indicating a perfect reconstruction of S0. The results also make it clear that the pure interference fringes do not include any component of intensity image, and thus the reconstructed polarization information does not contain any crosstalk signals. Moreover, the experimental results are in accordance with the theoretical expectation and the computer simulations. This research provides a novel means for spatially-modulated snapshot imaging polarization technology to obtain full-resolution object images and high-quality reconstructed polarization information.关键词
串扰/全分辨率/成像测偏技术Key words
crosstalk/full resolution/imaging polarimeter引用本文复制引用
张晶,任文艺,曹奇志,李建映,邓婷,Jin Ming-Wu..一种减少空间调制快拍成像测偏仪伪信息的方法[J].物理学报,2018,67(4):49-58,10.基金项目
国家自然科学基金(批准号: 11664004, 11504297, 41661085)、广西自然科学基金(批准号: 2016GXNSFAA380241)、陕西省科技厅项目(批准号: 2016KTZDGY05-02), 广西壮族自治区中青年教师基础能力提升项目(批准号: 2017KY0403)、北部湾环境演变与资源利用教育部重点实验室系统基金和广西师范学院博士启动基金资助的课题.Project supported by the National Natural Science Foundation of China (Grant Nos. 11664004, 11504297, 41661085), the National Natural Science Foundation of Guangxi, China (Grant No. 2016GXNSFAA380241), Shaanxi Science and Technology, China (Grant No. 2016KTZDGY05-02), Basic Ability Promotion Project of Guangxi Middle and Young Teachers in University, China (Grant No. 2017KY0403), Key Laboratory of Environment Change and Resources Use in Beibu Gulf, Ministry of Education, China (Guangxi Teachers Education University), and the Ph. D. Initial Fund of the Guangxi Teachers Education University, China. （批准号: 11664004, 11504297, 41661085）
