自由曲面光学元件具有许多优异的光学性能,越来越多地应用到现代光学系统设计中。而自由曲面光学元件制造的复杂性和不确定性是制约其应用的瓶颈之一。慢刀伺服单点金刚石车削是一种可以加工很高精度自由曲面光学表面或非回转对称光学曲面的新技术。机床伺服执行能力是自由曲面能否加工的基本条件。金刚石刀具几何参数的选择、刀具路径规划及刀具半径补偿是确保加工精度的关键。在理论上,对伺服执行能力进行了分析;发展了基于曲面特性分析的刀具参数确定方法;研究了稳定X轴的刀具圆弧半径补偿及刀具路径生成技术。使用慢刀伺服技术加工了多种典型的自由曲面光学元件,取得了较好的结果。

The inclusion of freeform elements in an optical system provides opportunities for numerous improvements in performance.However,designers are reluctant to utilize freeform surfaces due to the complexity and uncertainty of their fabrication.Single diamond turning is a novel machining process capable of generating freeform optical surfaces or rotationally non-symmetric surfaces at high levels of accuracy.In order to achieve good results with this technology some key parameters need to be satisfied.These parameters include tool geometry,tool path generation,tool radius correction,and servo system performance.The servo capacity of slow-tool-servo machine is analysed,and a method to determine tool geometry parameter based on surface analysis is developed.The methods of tool radius compensation and tool path generation to ensure the stability of X-axis are researched.Experiment results show that slow-tool-servo machining technology can be used in preparation of optical free form surfaces element.