3D Optical Metrology Laboratory, Department of Photonic Engineering, Chosun University, 309 Pilmun-Daero, Dong-gu, Gwangju 61452, Korea.
Sensors (Basel). 2021 Apr 17;21(8):2837. doi: 10.3390/s21082837.
In this investigation, we propose a motionless polarizing structured illumination microscopy as an axially sectioning and reflective-type device to measure the 3D surface profiles of specimens. Based on the spatial phase-shifting technique to obtain the visibility of the illumination pattern. Instead of using a grid, a Wollaston prism is used to generate the light pattern by the stable interference of two beams. As the polarization states of two beams are orthogonal with each other, a polarization pixelated CMOS camera can simultaneously obtain four phase-shifted patterns with the beams after passing through a quarter wave plate based on the spatial phase-shifting technique with polarization. In addition, a focus tunable lens is used to eliminate a mechanical moving part for the axial scanning of the specimen. In the experimental result, a step height sample and a concave mirror were measured with 0.05 µm and 0.2 mm repeatabilities of step height and the radius of curvature, respectively.
在这项研究中，我们提出了一种静止的偏光结构照明显微镜，作为一种轴向切片和反射式的装置，用于测量样品的三维表面轮廓。基于空间相移技术获得照明图案的可见度。我们使用渥拉斯顿棱镜代替网格来生成光图案，渥拉斯顿棱镜通过两束光的稳定干涉产生光图案。由于两束光的偏振态彼此正交，因此偏振分像素 CMOS 相机可以通过空间相移技术与偏振一起，在通过四分之一波片后同时获得四个相移图案。此外，我们使用调焦可调透镜消除了用于样品轴向扫描的机械移动部件。在实验结果中，我们对一个台阶高度样品和一个凹面镜进行了测量，台阶高度的重复性为 0.05 µm，曲率半径的重复性为 0.2 mm。
