一种超精密非球面在位测量方法

高面形精度非球面加工,离不开面形测量和误差补偿加工。离线测量容易导致工件装夹误差,并带来非加工时间增加。为解决这一问题,采用一种利用接触式的微小测头与激光干涉位移测量计相结合的在位形状测量装置,直接对磨削后的工件表面进行在位形状误差测量。介绍了该在位测量方法的原理及非球面测量过程,探讨了回转对称轴在半径方向的误差与测头倾角误差对测量误差的影响,并进行了补偿加工实验。对加工后的微小非球面进行了在位测量,并与超精密离线测量系统测量结果进行了比较。

An Ultra-Precision on-Machine Measurement Method of Aspheric Surface

High quality ultra-precise machining of aspheric surface includes machining,test,and compensation machining.In order to remove repeating installation error and decrease on-machine time of the aspheric surface,a contact on-machine measurement method is proposed in combination with a laser interferometer.Shape error of the ground surface is measured directly on the machine.The on-machine measuring principle and aspheric measuring process are studied.The measurement errors caused by positional deviation and inclination angle error are corrected in ultra-precise contact on-machine measurement process.A small aspheric surface after grinding is measured by the on-machine contact measurement method and the off-line measurement system,and the measuring results are compared to confirm the validity of the proposed method.