平面光学元件中频误差的磁流变加工控制  

Control of magnetorheological finishing on mid-spatial frequency error of flat optics

作　　者：颜浩[1] 唐才学[1] 罗子健[1] 温圣林[1] 

机构地区：[1]成都精密光学工程研究中心,四川成都610041

出　　处：《光学精密工程》2016年第12期3076-3082,共7页Optics and Precision Engineering

基　　金：中国工程物理研究院超精密加工技术重点实验室科研基金资助项目(No.ZZ15012)

摘　　要：为了利用磁流变加工实现对大口径平面光学元件波前中频误差的控制,研究了磁流变抛光去除函数的频谱误差校正能力和磁流变加工残余误差抑制方法。首先,比较了模拟加工前后元件中频功率谱密度(PSD1)误差和元件PSD曲线的变化,分析了磁流变去除函数的可修正频谱误差范围。然后,利用均匀去除方法分析了加工深度、加工轨迹间距和去除函数尺寸等磁流变加工参数对中频PSD2误差的影响,提出了抑制中频PSD2误差的方法。最后,对一块400mm×400mm口径平面元件的频谱误差进行了磁流变加工控制实验。实验显示:3次迭代加工后,该元件的波前PV由加工前的0.6λ收敛至0.1λ,中频PSD1误差由5.57nm收敛至1.36nm,PSD2由0.95nm变化至0.88nm。结果表明:通过优化磁流变加工参数并合理选择加工策略,可实现磁流变加工对大口径平面光学元件中频误差的收敛控制。To control the mid-spatial frequency error of a flat optics by Magnetorheological Finishing （MRF）, the correction ability of frequency error by the MRF removal function and the suppression method of residual error created by the MRF were investigated. Firstly, the changes of mid-spatial frequency PSD1 （Power Spectral Density 1）errors of the optics and the PSD curves before and after simulating the MRF were compared and the correctable frequency error range of the MRF removal function was analyzed. Then the effects of MRF processing parameters such as removal depth, tool- path intervals and the size of removal function on mid-spatial frequency PSD2 were analyzed based on uniform remove way and a method to suppress the mid-spatial frequency PSD2 error was established. Finally, the flat optics with a size of 400 mm× 400 mm was polished by the MRF. Experimental re- sults indicate that the wavefront PV of the flat optics is converged from 0.6 λ to 0.1 λ, the PSD1 error is converged from 5.57 nm to 1.36 nm, and the PSD2 error changes from 0.95 nm to 0.88 nm. It is concluded that the MRF has the abilities to control mid-spatial frequency error of large aperture flatoptics by optimizing and choosing MRF processing parameters and corresponding strategies.

关 键 词：磁流变加工 平面光学元件 中频误差 功率谱密度 去除函数 

分 类 号：TN305.2[电子电信—物理电子学] TH703[机械工程—仪器科学与技术]