鉴于彩色共聚焦测量技术无需做轴向扫描即可获得高度信息,且轴向分辨率能达到亚微米级、甚至纳米级,基于彩色相机的彩色共聚焦测量方法,提出一种颜色转换算法,并通过仿真对该算法进行优化,建立轴向高度与颜色的对应关系。经过实验分析,该颜色转换算法能够在轴向高度与颜色之间建立良好的线性关系,线性判断系数R2达到了0.9979;同时,对100 μm高度的台阶进行测量,测量精度达到了亚微米级;最后,对硬币表面进行测量和分析,修正了一系列误差后,较好地还原了硬币表面的三维形貌轮廓。

In this study, we propose a chromatic confocal measurement method that employs a color camera. The chromatic confocal measurement technology is extensively used in microscopic detection, biomedical applications, and other fields because of its sub-micron or even nanometer axial resolution and the advantage of obtaining height information without axial scanning. Furthermore, a color conversion algorithm is proposed and optimized by simulations to establish the corresponding relationship between the axial height and color. Experimental results indicate that the proposed color conversion algorithm can establish a good linearity between the axial height and color, and the linear judgment coefficient is R²=0.9979. We evaluate a step with a height of 100 μm and observe that the measurement accuracy can reach the sub-micron level. We also measure the coin surface and observe that our color conversion algorithm can reconstruct the three-dimensional surface topography of the coin after correcting a series of errors.