光电经纬仪主镜面型误差主动补偿技术研究

光电经纬仪俯仰动作时,引起主镜的面型误差,从而影响整个光学系统的准确度,以往主镜支撑结构采用被动式补偿方式,来保证实际面型最大误差在设计指标之内.本文基于压电陶瓷主动面型补偿技术,通过对俯仰变化引起面型误差曲线的实时修正,来主动控制主镜装调和动作引起的面型误差.使用光机系统联合仿真方法,拟合主镜面型误差,然后采用压电陶瓷的主动补偿技术修正面型误差,能够使原主镜峰值下降到66.9 nm,均方根最大值下降到12.9 nm,满足15.82 nm的均方根要求.基于压电陶瓷的主动面型补偿技术不仅可以很好地实时补偿主镜的动态面型误差,提高光学系统的像质清晰度和视轴稳定性,对大口径高准确度主镜系统的装调与动态检测有重要的意义.

Active Compensation Technology of Photoelectric Theodolite Primary Mirror Surface-shape Error

Primary mirror surface-shape error bringing flaw to optical system accuracy, which is caused by the pitching of large diameter photoelectric theodolite, is classified to center position error, off-center error and gravity deformation error. Previous design methods mostly are based on passive compensation, that is, design rational support and prevent deformation measures to assure the primary mirror surface-shape error within the design specifications. In this paper, piezoelectric ceramic active compensation technology is used to revise primary mirror surface-shape error with the method of real time correction on the surface-shape error induced by the pitching for large diameter photoelectric theodolite. Simulation software is utilized to fit the PV and RMS before and after compensation. The max PV value and max RMS decrease to 66.9 nm and 12.9 nm, respectively. Piezoelectric ceramic active compensation technology could bring benefit to image definition quality and the visual axis stability, making contribution to primary mirror surface-shape error on assembly and dynamic detection.