大型自由曲面光学器件的超精密抛光方法

旨在提高大尺寸自由曲面光学器件精密抛光技术的精度与效率。通过构建一个机器人抛光中心作为抛光平台,并在包括单位圆域、单位正方形域及自由边界域在内的平面映射域内求解旅行商问题,通过投影计算圆形度数值,进行映射区域的分类,并将所获得的平面轨迹映射到曲面上获得用于大尺寸自由度超精密光学器件的抛光路径。本文算法综合考虑到计算效率以及边界覆盖质量:当投影区域的圆形度超过0.9,则采用单位圆域作为映射平面域;当投影区域的圆形度值相对小,介于0.8与0.9之间,则采用单位方域作为映射平面域;当圆形度值小于0.8,则采用自由边界映射域。仿真及试验验证抛光结果表明,该方法可以获得高效的无交叉路径,有效降低单一方向运行导致的中频、高频误差,满足抛光路径方向不断变化的实际抛光加工需求,有效消除抛光纹理,并显著提高抛光精度和效率。

Ultra-Precision Polishing Method for Large Free-Form Surface Optics

This paper aims to improve the precision and efficiency of precision polishing technology for large-scale free-form surface optical devices.By constructing a robotic polishing center as a polishing platform,the travelling salesman problem is solved in a planar mapping domain including unit circle domain,unit square domain and free boundary domain.For the quotient problem,the circularity value is calculated by projection,the mapping area is classified,and the obtained planar trajectory is mapped to the curved surface to obtain the polishing path for the ultra-precision optical device with large-scale freedom.The algorithm in this paper takes into account the calculation efficiency and boundary coverage quality.When the circularity of the projection area exceeds 0.9,the unit circle domain is used as the mapping plane domain.when the circularity value of the projection area is relatively small,between 0.8 and 0.9,the unit square domain is used as the mapping plane domain.When the circularity value is less than 0.8,the free boundary mapping domain is adopted.Simulation and experimental verification of polishing results show that this method can obtain an efficient non-crossing path,effectively reduce the intermediate frequency and high frequency errors caused by a single direction operation,meet the actual polishing processing requirements of changing direction of the polishing path,effectively eliminate the polishing texture,and significantly improve the polishing accuracy and efficiency.