数控非接触式超光滑光学元件加工机床的设计

基于数控技术,提出了一种非接触式光学元件表面超光滑液体抛光方法.通过磨头中心孔为抛光表面提供抛光液,抛光液在磨头自转的带动下与光学元件表面相互作用,实现光学元件表面材料的微量去除,利用计算机控制抛光磨头的运动轨迹完成对光学元件表面的抛光.根据上述原理,设计和研制了数控非接触表面超光滑光学元件加工机床样机,样机直线运动轴最低进给速度为0.000 1 m/s,定位精度为0.008 mm；摆动轴最低转速为0.002 8 r/min,定位精度为15″.抛光实验结果表明,经过20 min的超光滑加工,熔石英材质光学元件上两点的表面粗糙度Ra值分别由加工前的1.03 nm和0.92 nm提高到加工后的0.48 nm和0.44 nm,显著提高了加工精度.

Design of CNC non-contact super-smooth polishing machine for optical components

A Computer Numerical Control(CNC) non-contact super-smooth polishing method for optical components was proposed.Polishing fluid was provided through a center hole of the polishing tool for the optical surface and it interacted with the surfaces of optical components drived by a rotated polishing tool to remove the materials on the optical components minutely.The motion trajectory of the polishing tool could be controlled by the computer.According to the proposed principle,a prototype of CNC non-contact super-smooth polishing machine for the optical components was designed and developed,and its minimum feed rate and positioning accuracy for the linear motion axis are 0.000 1 m/s and 0.008 mm,respectively;the minimum rotate speed and positioning accuracy for the swing shaft are 0.002 8 r/min and 15′,respectively.The performance of the prototype could meet the requirements of spherical/aspherical optical components with diameters less than 200 mm for super-smooth polishing.To verify the prototype,an experiment was performed on a fused silica component.After super-smooth polishing for 20 min,the surface roughness of two points on the optical component is improved from 1.03 nm and 0.92 nm to 0.48 nm and 0.44 nm,which shows the polishing accuracy has been optimized greatly.