基于空间频率评价磁流变抛光非球面中频误差  

Error-regulating method for magnetorheological finished aspherics focused on spatial frequency

作　　者：程灏波[1] 

机构地区：[1]清华大学精密仪器与机械学系

出　　处：《哈尔滨工业大学学报》2006年第6期917-919,1012,共4页Journal of Harbin Institute of Technology

基　　金：国家高技术研究发展计划资助项目(2001AA421140);国家自然科学基金资助项目(50175062)

摘　　要：基于空间频率的概念,提出磁流变抛光非球面表面波像差的相移评价算法,根据位相与表面高度差之间的关系,计算出元件表面上各点的实际高度差.通过规划表面残余误差与抛光工艺参数之间的关系,确定能够有效消除表面残余误差的磁流变抛光工艺规范,制造成功在20 mm通光口径内面形精度达到20 nmRMS(均方根值)的非球面曲面.该方法克服了传统评价方法的局限性,为深入开展纳米精度磁流变抛光技术提供有力的技术储备.A phase-shifting algorithm is proposed for evaluating the residual errors on the surface of components after magnetorheological finishing, which deduces the actual wavefront errors by calculating optical the relationship between sag errors and phase in view of spatial frequency. According to this model, a parabolic mirror was manufactured to a finally shape accuracy achieve to 20 nanometer within 20 millimeter aperture by optimizing the relative parameters such as tool path step, rotation speed of the polishing wheel and density of the magnetic field. Experimental results present that the model can overcome the limitation of traditional evaluating means, and provide powerful technical storage for studying magnetorheological finishing technology with nanometer accuracy thoroughly.

关 键 词：相移 干涉检测 抛光 非球面 空间频率 

分 类 号：TH744.3[机械工程—光学工程]