单元件干涉数字全息的光线追迹模型

基于棱镜对的单元件干涉可以获得透射物体的相位信息，即数字全息，具有结构紧凑、干涉条纹稳定、测量精度高等优点。采用光线追迹方法，综合考虑了棱镜对的方位角旋转、斜面偏心等参数，建立了光线追迹等效模型，仿真了数字全息干涉条纹，给出了条纹密度变化及倾斜的解析表达式。针对单模和多模光纤等微结构光学元件，获得了干涉数字全息图，并反演出其折射率分布。搭建了显微成像单元件干涉实验装置，获得了实际测量干涉图样，实验与仿真结果一致，证明了本模型的有效性。

Ray tracing model of digital holography with single element interference

The phase information of the transmitted object, also known as digital holography, can be obtained by the element interference based on prism pair. This method has the advantages of compact structure, stable interference fringe and high measurement accuracy. In this paper, the ray tracing method is used to establish the equivalent model of ray tracing, considering the azimuth rotation of the prism pair and the eccentricity of the inclined plane. The equivalent model is used to simulate the digital holographic interference fringes, and give the analytic expressions of fringe density change and tilt. The interference digital holograms are obtained and the refractive index distribution is inversed for the micro structure optical elements such as single-mode and multimode fibers. The experimental device of micro imaging unit interference is built, and the actual measurement interference pattern is obtained. The experimental results are consistent with the simulation results, which proves the effectiveness of this model.