Zhang Hao, Wang Peng, Li Zexiao, Shen Yi, Zhang Xiaodong
State Key Laboratory of Precision Measuring Technology & Instruments, Centre of Micro Nano Manufacturing Technology, Tianjin University, Tianjin 300072, China.
Tianjin Jinhang Institute of Technical Physics, Tianjin 300308, China.
Micromachines (Basel). 2020 Oct 15;11(10):938. doi: 10.3390/mi11100938.
Although the high-speed polishing technology has been widely applied to obtain an ultra-smooth surface in the field of spherical optical manufacture, it is still mainly used in small-size or easily polished lenses. In the infrared optical system, large-size silicon lenses are often used to increase the luminous flux. As is known, the material is hard-polished, it is time-consuming to reduce the surface roughness by iterative polishing and it is difficult to avoid the form accuracy getting worse. To produce an ultra-smooth surface efficiently without destroying the figure, a scientific understanding of material removal in the high-speed polishing process is necessary, which would lead to the process being more deterministic. In this paper, a mathematical model of material removal is developed based on the classic Preston equation. The predicted results of the proposed model show good agreement with the experimental data. Further, a method to achieve uniform polishing can be addressed with a systematic analysis of the key factors affecting material removal and their contribution to spatial non-uniform removal. Finally, the experimental results indicate that the surface roughness of hard-polished spherical optics can be improved efficiently using the uniform polishing method without the surface figure being destroyed.
尽管高速抛光技术已在球面光学制造领域广泛应用以获得超光滑表面，但它仍主要用于小尺寸或易于抛光的透镜。在红外光学系统中，常使用大尺寸硅透镜来增加光通量。众所周知，该材料难以抛光，通过反复抛光降低表面粗糙度耗时且难以避免形状精度变差。为了在不破坏形状的情况下高效地产生超光滑表面，有必要科学地理解高速抛光过程中的材料去除情况，这将使该过程更具确定性。本文基于经典的普雷斯顿方程建立了材料去除的数学模型。所提模型的预测结果与实验数据吻合良好。此外，通过系统分析影响材料去除的关键因素及其对空间不均匀去除的贡献，可以找到实现均匀抛光的方法。最后，实验结果表明，使用均匀抛光方法可以有效提高硬抛光球面光学元件的表面粗糙度，且不会破坏表面形状。
