单晶锗光学表面数控高速抛光优化试验

Optimization experiment on high speed numerical control polishing of single crystal germanium

摘要:

为研究单晶锗镜片表面光洁度无法达到要求的加工技术难题,基于数控高速抛光方法,开展了聚氨酯和沥青两种抛光模的数控高速抛光优化试验,以Preston理论为基础,通过不断优化工艺流程和参数,结合运动轨迹仿真和功率谱密度计算,对比分析了两种抛光模的加工效率和表面质量控制能力. 试验结果表明:两种抛光方式均能获得较高的面形精度,聚氨酯抛光模具有较高的加工效率,但光学表面微观形貌控制能力较差,沥青模抛光得到的表面粗糙度 RMS相比聚氨酯模提升近3 nm. 通过单晶锗光学表面数控高速抛光试验,最终优化并提出了聚氨酯初抛光与沥青精抛光相结合的方式,并进行了试验验证.

Abstract:

To solve the technical problem that the surface finish of single crystal germanium lens cannot meet requirements, this paper carries out numerical control high-speed polishing optimization tests on polyurethane and asphalt polishing molds based on the numerical control high-speed polishing technique. According to the Preston theory, the processing efficiency and the surface quality control ability of the two polishing molds were compared and analyzed through continuous optimization of process flow and parameters with the combination of motion trajectory simulation and power spectral density calculation. Experimental results show that both of the polishing molds obtained high surface accuracies. The polyurethane mold had higher processing efficiency, but its ability to control the microstructure of the surface was poor. The surface roughness RMS of the asphalt polishing mold improved nearly 3 nm compared with that of the polyurethane polishing mold. Finally, after optimization, the combination of polyurethane initial polishing and asphalt polishing technique was proposed and verified by experiments.