提出了一种利用光学共轭关系,实现多变形镜空间匹配从而提高波前空间校正能力的自适应光学系统方案。通过理论分析给出了组合变形镜的面形描述方法,在此基础上建立了一套基于由两块相同方形排列变形镜构成的组合波前校正器的完整自适应光学实验系统。通过数值仿真研究了该系统对前35阶Zernike像差的校正效果,并且通过实验对比了组合变形镜和单一变形镜对实际静态像差的闭环校正效果。结果表明组合变形镜可以等效为一多单元变形镜,在直接斜率控制算法下正常稳定闭环工作,校正效果明显优于单一变形镜。组合变形镜技术通过空间匹配实现了增加波前校正器驱动单元数和等效交连值,有效地提高了对波前的空间校正能力,因此可以代替高成本的单一多驱动器变形镜用于自适应光学系统中高阶像差的校正。

A new kind of adaptive optics (AO) system, in which several deformable mirrors (DMs) with optical conjugation relationship are combined to improve wavefront spatial correction capability, is proposed. The surface displacement of combinational deformable mirror (CDM) is introduced. Based on theoretical analysis, the integrated AO system with CDM that consists of two same deformable mirrors with the square arrays is built. The correction performance for the first 35 order Zernike aberrations is calculated and its closed-loop effect for correcting real aberrations is validated experimentally. The results indicate that CDM in the AO system can correct aberrations effectively as the same as one single DM with more actuators by using the direct-gradient control algorithm steadily in closed-loop, and the correction capability of the CDM is better than that of only one DM. This design can improve wavefront spatial correction capability by increasing the number of actuators and the coupling coefficient. So it can be used for compensating high-order aberrations instead of one single costly DM with more actuators for the same performance.