超精密加工过程存在的加工误差影响着器件的面形误差,进而影响光学性能。制造者往往从面形精度方面来评价加工精度,但是光学性能才是光学系统的最终评价指标,仅仅关注加工过程中加工误差对单个面的面形误差影响是不够的,加工误差对系统光学性能的影响需要进一步研究。基于多体系统理论和光线追迹理论建立了加工误差影响分析模型,探索了加工误差对面形误差和光学性能的影响,得出了系统主要的面形误差形式及其对系统调制传递函数(MTF)的影响关系,并根据系统对光学性能的要求得出了加工误差、面形误差和角度公差,从而找到了影响三反系统光学性能的重点加工误差,研究结果可为离轴三反系统加工误差的控制及光学质量可控制造的实现提供理论指导。

There are many machining errors in the ultra-precision machining process that affect the surface-shape error of devices, so they also affect the optical performance. Manufacturers always evaluate machining accuracy based on surface form accuracy. But optical performance is the final evaluated index for the optical system, so it is insufficient to evaluate the effect of the machining error on the surface-shape error of only one mirror in machining process. The effect of machining error on optical performance needs further research. Analysis model of machining error influence is established based on the multi-body system theory and the optical ray tracing theory. The effect of the machining errors on the surface-shape error and the optical performance is researched. The main form of the surface-shape error in the system and its influences on modulation transfer function (MTF) are obtained. Then, the tolerance of the machining errors,main surface-shape error and angle error are obtained based on the requirements of optical performance. The main machining errors are found, which affect the optical performances of three-mirror system. The results provide a theoretical support to the control of the main machining errors and the realization of the performance-controllable manufacture for the off-axis three-mirror system.