应用双摆动技术加工离轴碳化硅反射镜

研究了用双摆动技术抛光离轴非球面的工艺。介绍了用双摆动抛光加工离轴非球面的原理,分析了双摆动抛光过程中抛光盘与工件的相对运动特性及各个工艺参数对相对运动路径的影响。建立了双摆动抛光运动的数学模型,进行了计算机仿真,并对不同参数下的仿真结果进行了比较。给出了抛光模形状模型,实验验证了不同形状抛光模的材料去除特性。应用双摆动技术加工了一个224mm×108mm离轴碳化硅反射镜,结果显示:应用该技术加工离轴非球面镜可以有效抑制光学表面中频误差,具有较高的材料去除效率,面形精度可以稳定达到λ/30(rms,@633nm)。因此,双摆动抛光技术的研究有助于推动离轴非球面制造技术的发展。

Manufacture of SiC off-axis aspheric mirrors by double-swing method

The polishing principle of Double-Swing Method (DSM) was introduced, the relative movement characteristic between polishing lap and workpiece was analyzed, and the influence of polishing parameters on the relative movement was discussed. A mathematical model of the DSM in a movement state was established and its movement was simulated in a programming language. Then, simulation effects under different parameters was compared. The shape model of the polishing lap was presented, and the material removal character of the polishing lap with diffident shapes was verified.Finally,a rectangle off-axis aspheric mirror in a size of 224 mm×108 mm was polished by the DSM. The experiment result shows that to manufacture the off-axis aspheric mirror by the DSM can control the middle-frequency error and can obtain high working efficiency, and the surface precision is about λ/30 (rms, @633nm). Therefore, the DSM benefits the development of the manufacture technique for off-axis aspheric mirrors.