Liao Defeng, Xie Ruiqing, Zhao Shijie, Xu Qiao
Appl Opt. 2023 Jun 10;62(17):4551-4556. doi: 10.1364/AO.490157.
Full-aperture continuous polishing using a pitch lap is one of the key processes in finishing large flat optical elements. The pitch lap has relief lines cutting into the surface to increase its surface roughness and to improve the polishing results. During polishing, the pitch lap surface is glazed due to the transverse rheologic flow and creep of the pitch lap by the element and conditioner, which has significant influence on the polishing results. In this study, an image texture analysis method is proposed to monitor the glazing state of the pitch lap. The images of the pitch lap surface are captured online, and the image textures are analyzed with the gray level co-occurrence matrix (GLCM) method. The experiments revealed that the GLCM eigenvalues of the surface image are strongly correlative with the glazing state of the pitch lap, which has a linear impact on the material removal rate and material removal uniformity. To the best of our knowledge, this study provides a novel and useful method to monitor the surface glazing state of the pitch lap.
使用沥青研磨盘进行全孔径连续抛光是大型平面光学元件精加工中的关键工艺之一。沥青研磨盘表面有切入表面的纹路，以增加其表面粗糙度并改善抛光效果。在抛光过程中，由于元件和修整器对沥青研磨盘的横向流变流动和蠕变作用，沥青研磨盘表面会产生釉化现象，这对抛光效果有显著影响。在本研究中，提出了一种图像纹理分析方法来监测沥青研磨盘的釉化状态。在线采集沥青研磨盘表面的图像，并采用灰度共生矩阵（GLCM）方法对图像纹理进行分析。实验表明，表面图像的GLCM特征值与沥青研磨盘的釉化状态密切相关，对材料去除率和材料去除均匀性有线性影响。据我们所知，本研究提供了一种新颖且有用的方法来监测沥青研磨盘的表面釉化状态。
