色散物镜是光谱共焦显微镜的关键组件, 其轴向色散线性度和色散范围会影响光谱共焦显微镜的性能。在线性轴向色散的理论基础上, 研究了优化选择材料组合的方法, 给出了优化模型和求解方法, 得到了具有最大色散的材料组合及其光焦度分配, 并使用光学设计软件对优化结果进行了模拟。模拟结果表明, 使用本文优化方法得到的材料组合, 波长与轴向色散成线性关系, 而且具有最大的轴向色散。使用得到的最大色散材料组合进行色散物镜设计, 得到了较好线性度的色散物镜, 并具有较短的有效焦距。本文给出的优化选择材料组合的方法可以为设计光谱共焦显微镜提供指导, 有效缩短镜筒长度, 提高光谱共焦显微镜的性能。

Dispersive objective is the key component of Chromatic Confocal Microscope (CCM). The measuring range of CCM depends on the chromatic aberration of dispersive objective, and the nonlinear axial chromatic aberration of dispersive objective would lower the sensitivity of CCM. To achieve large axial chromatic aberration, optimization method of selecting materials combination is proposed based on the principle of linear axial chromatic aberration. The optimization model is presented and solved to get the optimal solutions, which are the materials combinations of largest linear axial chromatic aberration. The results from optical design software indicate that lenses of optimal materials combinations could achieve largest linear axial chromatic aberration among the glass catalog. With the optimal materials combination, a dispersive objective was designed for CCM. The well designed objective could provide large linear measuring range while having a short tube length. Optimization and selection of materials are significant for dispersive objective design to heighten the performance of CCM.