环形抛光是大口径平面光学材料加工的首选方式,特别是在大口径平面光学元件的超精密加工中占有重要地位。抛光盘表面形状是影响元件面形精度的直接因素。为了研究小工具对抛光盘表面材料的去除特性,首先需要准确测得抛光盘的表面形状。采用激光位移传感器采集抛光盘表面螺旋样点的高度,针对实验检测误差进行分析并标定,最终计算得到抛光盘表面的实际形状。借鉴数控小工具抛光方法,建立小工具修正下抛光盘的材料去除模型,通过仿真计算得到了在小工具修正范围内抛光盘的材料去除函数,分析了抛光盘的材料去除特性。最后通过小工具修正实验验证了仿真结果的正确性,为抛光盘的形状修正提供理论依据。

Continuous polishing is the preferred method for processing large-aperture planar optical materials, especially playing an important role in ultra-precision processing of optics. The surface accuracy of components is directly affected by the surface shape of the polishing pad. To study the removal characteristics of polishing-pad surface materials with small-tools, accurately measuring the surface shape of the polishing pad is necessary. In this paper, the height of spiral sample points on the surface of a polishing pad is collected by laser displacement sensor, and the experimental detection errors are analyzed and calibrated. Subsequently, the actual shape of the polishing pad surface is calculated. Using a computer controlled polishing method for reference, the material-removal model of the polishing pad with tool correction is established, the material removal function of the pad in the correction range of the small-tool is simulated and calculated, and the material-removal characteristics of the polishing pad are analyzed. Finally, the correctness of the simulation results is verified with a small-tool correction experiment, which provides a theoretical basis for shape modification of the polishing pad.