光学镜面离子束加工去除函数工艺可控性分析

实验分析了离子束加工去除函数的工艺可控性问题并进行了初步修形实验。从工艺实现的角度分析光学镜面离子束加工技术对去除函数的要求,以去除函数环半峰全宽、体积去除率和峰值去除率为评价指标研究去除函数的长时稳定性、线性性、小扰动鲁棒性以及大参数调节变化等特征,以此分析结果为依据,对Φ100mm K4平面样件进行了修形,经过三次迭代面形RMS误差从0.149λ收敛到0.013λ。实验结果表明:离子束加工中的去除函数具有较长时稳定性,去除量对时间具有线性关系,对工艺参数小扰动的鲁棒性,可以通过调节离子源电源参数优化选取去除函数的宽度和幅值;利用离子束可以对镜面进行高效地修形。

Controllability of removal function in the ion beam figuring process for optics mirrors

The processing controllability of the removal function is analyzed experimentally and then figuring experiment is made on the plane sample of K4.The demands on the removal function are deduced from the CCOS principle.Three factors CFWHM,volume removal rate and peak removal rate are presented to evaluate the properties of the removal function,which are the long-time stability,time linearity,robust with respect to little disturbance of process parameters.The influences of parameters adjustment in large scale on the removal function are analyzed.Based on the results on the removal function,the Φ100mm K4 sample is figured with ion beam.With three iterations,the surface error is reduced from 0.149λ RMS to 0.013λ RMS.The experimental results indicate that the removal function can hold a long-time stability,scale with time,have robust with respect to little disturbance.The width and removal rate can be modulated by process parameters.Ion beam figuring is a technique of high efficiency.