基于波前复制方法的自适应光学系统静态像差校正技术
Static Aberration Correction Technique in Adaptive Optical Systems Based on Wavefront Replication Method
-
摘要: 由波前传感器所在的波前传感路径与科学相机所在成像路径之间的差异引起的非共光路像差(Non-Common Path Aberration, NCPA)是制约自适应光学系统(Adaptive Optics, AO)达到衍射极限成像性能的关键因素之一. 同时, AO系统中共同光路部分中的光学组件也会引入静态像差. 为抑制自适应光学系统中的静态像差, 使用一种基于波前相位模板复现的技术. 该技术使用激光光源在科学成像光路中夏克哈特曼波前传感器(Shack-Hartmann Wavefront sensor)上产生的完美波前图像作为参考波前信息, 并以此参考波前信息为优化目标, 通过迭代优化算法生成变形镜控制命令, 将科学成像光路的波前优化到与参考波前一致. 实验结果表明, 即使在AO系统存在较大初始静态像差的情况下, 此技术依然可以稳定地获得全局优化校正结果, 将系统的斯特列尔比(Strehl Ratio, SR)从校正前的0.309提高到0.995.Abstract: Non-Common Path Aberration (NCPA), arising from the optical path difference between the wavefront sensing branch containing the wavefront sensor and the scientific imaging branch containing the science camera, is a fundamental limitation preventing Adaptive Optics (AO) systems from achieving diffraction-limited performance. Furthermore, static aberrations are introduced by optical elements within the common path of the AO system. To suppress the static aberration in the adaptive optics system, this paper introduces a technique based on wavefront phase template reproduction. The method employs a laser light source to generate an ideal wavefront pattern on the Shack-Hartmann wavefront sensor within the scientific imaging path, which serves as a reference wavefront. This reference wavefront is then used as the optimization target. Through an iterative optimization algorithm, control commands for the deformable mirror are generated to drive the scientific imaging path's wavefront to converge with the reference. Experimental results indicate that this technique robustly achieves global optimization, even in the presence of substantial initial static aberrations, enhancing the system's Strehl Ratio (SR) from 0.309 to 0.995 post-correction.
下载: