应用多模式组合加工技术修正大口径非球面环带误差

Zonal error removal for large aspheric with multi-mode combined manufacture technique

为了满足大口径非球面光学元件加工的需求,提出了用多模式组合加工(MCM)技术修正大口径非球面反射镜环带误差的方法。本文讨论的MCM技术以经典加工工艺为基础,采用抛光盘的多工位加工和抛光模式的组合完成光学元件的抛光,实现对光学表面中低频段误差的有效控制。介绍了MCM技术的重要组成部分JP-01抛光机械手的工作原理,分析了MCM的工作模式。采用MCM技术对Φ1230mm的非球面反射镜进行环带误差的修正,给出了镜面面形检测结果。实验结果表明,MCM技术可以有效地控制光学表面的中低频误差,使光学表面误差得到有效收敛,从而显著提高抛光效率。目前,采用MCM技术加工1～2m口径的同轴非球面,其精度可以达到30nm(RMS)。

In order to satisfy the requirements of large mirrors for the fabrication precision,the removal of zonal errors for a large aspheric is analyzed with the Multi-mode Combined Manufacture （MCM） technique in this study.The MCM technology discussed is based on the traditional fabrication theory,in which the multi-mode machining combined the multiple polishing of the laps is used to finish the optical component to control the low and middle frequency errors effectively of the optical surface.The principle of JP-01 polishing manipulator which is an important part of the MCM technology is presented,and the working mode of MCM is analyzed in detail.Finally,the MCM technology is used to deal with the zonal error of an aspheric with the aperture of 1 230 mm.The experimental results show that the MCM technology can control the low and middle frequency errors of the optical surface effectively,constrain the surface error and improve the polishing efficiency observably.At present,the precision of a large on-axis mirror with the aperture of 1-2 m has reached 30 nm（RMS）.These results prove that the MCM can be one of the important technologies for the development of the large mirror manufacture.