高精度非接触式位移传感器有着广泛的应用。本文讨论其中一种采用光学方法实现非接触测量的光谱共焦位移传感器，阐述该传感器的工作原理，给出了该系统的设计方法和评价方法。最后基于光学设计软件CODE V的宏语言和数学软件MATLAB 设计出了一个测量范围为0~1.173 mm 的光谱共焦位移传感器物镜。该物镜采用一个单透镜和双胶合透镜组合的结构，在工作波长范围内，各个单波长对应最大的RMS 半径为2.8 μm，其测量精度优于5 μm，波长离焦量和波长之间线性度通过线性回归拟合得出判定系数为0.985 9，测量的线性度优异。

Since non-contacting displacement sensors with high precision have been used widely, this paper presents one of examples, which is the spectral confocal displacement sensor. Firstly, the working principle of the sensor is described, and then the design and evaluation schema of the system is proposed. Finally, we design a specific case of the spectral confocal displacement sensor objective lens based on CODE V macro language and MATLAB. The sensor whose work-distance is 0~1.173 mm has the measuring accuracy better than 5 μm. The lens is combined with a single lens and doublet lens. In the work wavelength, each single-wavelength has the corresponding largest RMS radius of 2.8 μm. Through linear regression fitting of the defocusing amount and linearity of the wavelength, it is obtained that the coefficient of determination is 0.985 9. So the linearity of measurement is well.