根据光谱共焦位移传感器的工作原理及线性轴向色散条件,选择3种色散物镜用玻璃材料N-KZFS11、N-SF66和N-PK52A,并结合像差理论设计了由3个单透镜和2个双胶合透镜组合成的线性色散物镜初始结构。利用Zemax光学设计软件对色散物镜的初始结构进行优化和公差分析。结果表明:在450~650 nm波长范围内,各波长弥散斑均远小于艾里斑,色散物镜测量范围可达1.05 mm,轴向色散与波长之间的线性判定系数R²达0.997,理论分辨率可达105 nm。

In this study, the working principle of the chromatic confocal displacement sensor and the conditions of linear axial dispersion were applied for the optimal selection of three kinds of glass materials, namely N-KZFS11, N-SF66, and N-PK52A, which were combined with the theory of aberration to design the initial structure of a linear dispersive objective composed of three single lenses and two double cemented lenses. Then, the Zemax software was used to optimize the initial structure of the dispersive objective and analyze its tolerance. The results indicate that within the wavelength range from 450 nm to 650 nm, the blur spot at each wavelength is much smaller than the Airy spot. The measurement range of the dispersive objective is up to 1.05 mm, the linear determination coefficient R2 between the axial dispersion and wavelength is 0.997, and the theoretical resolution could reach 105 nm.