空间调制外差干涉型偏振光谱测量系统

Spectropolarimetric measurement system based on spatially modulated heterodyne interference

鉴于偏振光谱仪系统追求的目标是高偏振光谱分辨率、全Stokes谱静态测量、兼顾小体积轻质量,结合偏振光谱强度调制技术与空间外差干涉技术,提出空间调制外差干涉型偏振光谱仪系统。介绍了空间调制外差干涉型偏振光谱仪系统的结构原理,并对系统干涉图数据采集和全Stokes矢量解调复原进行了理论分析,给出了完整数学推导。结合空间外差光谱仪参数,匹配设计了调制器模块,给出一套完整的设计实例。在实验室搭台建立空间调制外差干涉型偏振光谱仪原理实验装置,通过对已知偏振态线偏振光的测量实验以及实验数据解析,验证系统原理及测量数据处理流程的正确性。结果表明:几种已知偏振态的线偏振光,由实验装置测量数据解析得到的Stokes矢量谱与理论分析结果基本一致,误差小于3%,验证了空间调制外差干涉型偏振光谱获取技术的可行性。

The design goals of a spectropolarimetric system are higher spectropolarimetric resolution,a smaller and lighter system,and static measurement of the full Stokes spectrum.Therefore,the spatially modulated heterodyne interference spectropolarimetric system,which combines the technologies of intensity modulation and spatial heterodyne was proposed.While the process of all mathematical derivation was displayed,the principle and structure of the system were presented and a theoretical analysis of the interferogram data acquisition and full Stokes parameters demodulation restoration was carried out.The matching modulator module was designed and a complete design example was finished based on the parameters of the spatial heterodyne spectrometer used.A principle experimental device of spatially modulated heterodyne interference spectropolarimetric system was established in the laboratory,and the feasibility of the principle and measurement data processing flow of the system was verified by analyzing the measurementexperiments and experimental data of linearly polarized light with a known polarization state. The measurement and analysis results of the experimental data are consistent with the theoretical results, and the erroris less than 3% This verifies the feasibility of principle of the spatial modulation heterodyne interferencespectropolarimetric system.