Wang Bo, Tie Guipeng, Shi Feng, Song Ci, Guo Shuangpeng
Opt Express. 2023 Oct 9;31(21):35016-35031. doi: 10.1364/OE.501830.
With the continuous development of modern optical systems, the demand for full spatial frequency errors of optical components in the system is increasing. Although computer-controlled sub-aperture polishing technology can quickly correct low-frequency errors, this technology significantly worsens the mid-frequency errors on the surface of the component, which greatly inhibits the improvement of optical system performance. Therefore, we conducted in-depth research on the non-stationary effect of the removal function caused by the fluctuation in magnetorheological polishing and their influence on the mid-frequency errors of the component surface. We established a non-stationary profile model of the removal function and applied this model to simulate the distribution of mid-frequency errors on the surface of the processed component, considering the non-stationary effect. The simulation results showed that the non-stationary effect of the removal function weaken the mid-frequency ripple errors but increase other mid-frequency errors. Therefore, we first proposed the optimal single-material removal thickness corresponding to the non-stationary effect and experimentally verified the effectiveness of the optimal material removal thickness in suppressing mid-frequency errors. The experimental results showed that when the magnetorheological finishing single-material removal thickness is set to the optimal value, both the mid-frequency ripple errors and the mid-frequency RMS on the surface significantly decrease. Therefore, this work provides a basis for improving the existing magnetorheological finishing process and effectively suppressing the mid-frequency errors on the surface of processed components. It also provides theoretical and technical support for the magnetorheological processing and manufacturing of high-precision optical components. At the same time, the non-stationary effect and the corresponding analytical models has the potential to be extended to other polishing tools.
随着现代光学系统的不断发展，系统对光学元件全空间频率误差的要求日益提高。尽管计算机控制的子孔径抛光技术能够快速校正低频误差，但该技术会显著恶化元件表面的中频误差，极大地抑制了光学系统性能的提升。因此，我们针对磁流变抛光中波动引起的去除函数非平稳效应及其对元件表面中频误差的影响展开了深入研究。我们建立了去除函数的非平稳轮廓模型，并将该模型应用于模拟考虑非平稳效应时加工元件表面中频误差的分布。模拟结果表明，去除函数的非平稳效应减弱了中频波纹误差，但增加了其他中频误差。因此，我们首次提出了对应非平稳效应的最佳单材料去除厚度，并通过实验验证了最佳材料去除厚度在抑制中频误差方面的有效性。实验结果表明，当将磁流变精修单材料去除厚度设置为最佳值时，表面的中频波纹误差和中频均方根值均显著降低。因此，这项工作为改进现有的磁流变精修工艺和有效抑制加工元件表面的中频误差提供了依据。它也为高精度光学元件的磁流变加工制造提供了理论和技术支持。同时，非平稳效应及相应的解析模型有潜力扩展到其他抛光工具。
