Finishing of optical moulds to λ/20 by automated corrective polishing
Finishing of optical moulds to λ/20 by automated corrective polishing
复制标题
DOI：
10.1016/j.cirp.2011.03.110
复制
发表时间：
2011-01-01
影响因子：
4.1
通讯作者：
Freeman, R.
中科院分区：
文献类型：
--
作者：
Beaucamp, A.;Namba, Y.;Freeman, R.
碳化钨广泛用于制造小型非球面和自由曲面光学元件（如相机镜头）的复制模具。由于通过研磨生成非球面通常无法达到超精密标准，因此需要一种高效的模具精加工方法。利用一台七轴数控抛光机，开发了一种机上刀具成型技术和补偿软件，用于在1小时内对直径为25毫米的平面碳化钨表面进行矫正抛光，将形状误差从大于λ降低到小于λ/20（峰谷值为29纳米），同时将粗糙度降低到1.0纳米Ra。这种自动方法和工具适用于非球面和自由曲面模具。（C）2011年国际生产工程科学院（CIRP）
Tungsten carbide is widely used to make replication moulds for small aspheric and freeform optics, like camera lenses. Since aspheric generation by grinding generally fails to reach ultra-precision criteria, a time efficient method for finishing moulds is needed. Using a 7-axis CNC polishing machine, an on-machine tool forming technique and compensation software were developed to correctively polish a piano WC surface of diameter 25 mm from a form error above lambda to below lambda/20 (29 nm P-V) in under 1 h, while reducing roughness to 1.0 nm Ra. This automatic method and tooling are applicable to aspheric and freeform moulds. (C) 2011 CIRP.