Yang Xin, Guo Renhui, Tang Xing, Yin Zhiyao, Liu Chengxing, Li Jianxin
Appl Opt. 2021 Dec 20;60(36):10988-10995. doi: 10.1364/AO.441563.
In this study, we proposed a point diffraction interferometer based on birefringence polarization beam splitting (BPBS-PDI) for transmission wavefront measurements. Using the polarization beam splitting property of birefringent crystals and a specially designed calcite crystal as a polarization beam splitter, two beams of linearly polarized light with orthogonal polarization directions and a small angular separation can be obtained to produce the reference and test beams with perpendicular polarization directions through a pinhole point diffraction plate. By introducing spatial synchronization phase-shifting technology, influencing factors such as environmental vibrations on the measurement results, are reduced. Subsequently, the birefringent crystal and system error calibration methods were studied. Finally, a BPBS-PDI experimental device was set up to obtain the wavefront distribution of the lens to be tested. The experimental results are consistent with those of the ZYGO interferometer, indicating that the BPBS-PDI wavefront measurement method can be used to measure a lens transmission wavefront with high accuracy.
在本研究中，我们提出了一种基于双折射偏振分束（BPBS-PDI）的点衍射干涉仪，用于透射波前测量。利用双折射晶体的偏振分束特性，并采用一块特殊设计的方解石晶体作为偏振分束器，可获得两束具有正交偏振方向且夹角较小的线偏振光，通过针孔点衍射板产生偏振方向相互垂直的参考光束和测试光束。通过引入空间同步相移技术，减少了环境振动等对测量结果的影响因素。随后，研究了双折射晶体及系统误差校准方法。最后，搭建了BPBS-PDI实验装置，获取了待测透镜的波前分布。实验结果与ZYGO干涉仪的结果一致，表明BPBS-PDI波前测量方法可用于高精度测量透镜的透射波前。
