基于普适模型的无波前探测自适应光学系统仿真与分析

Simulation and Analysis of General Model-Based Wave-Front Sensorless Adaptive Optics System

为了提高基于普适模型的无波前探测自适应光学(AO)算法的收敛性能,建立了一套基于Zernike模式的127单元变形镜AO系统仿真模型。以峰值斯特列尔比(Sr)和提出的快速稳定收敛百分比为评价标准,研究不同湍流强度下扰动系数、Zernike模式数、斜率因子对校正效果和收敛速度的影响,验证了该仿真系统对静态畸变波前良好的校正能力。结果表明,扰动系数小于0.01时系统可以稳定收敛;增加Zernike模式数可以提高系统收敛时的Sr,但同时收敛速度会有所降低。提出的改进矢量化斜率因子,可以有效提升系统在一次迭代后的校正效果,特别是对大畸变波前具有较强的适应性。

To improve the convergence ability of a wave-front sensorless adaptive optics （AO） algorithm using ageneral model-based approach, an AO system simulation model based on Zernike modes is established with a 127-elements deformable mirror （DM）. Using peak Strehl ratio （Sr） and the proposed fast-steady-convergencepercentage as evaluation criterion, good correction capability for static distorted wave-front is verified by analyzingthe impact of different perturbation coefficient, the number of Zernike modes, and slope factor on correction effectand convergence speed under different turbulence intensity. The results show that when the perturbation coefficientis less than 0.01, the system can converge steadily and increasing the number of Zernike modes can ascend Sr of theconvergence while it will sacrifice some convergence speed. A modified vector slope factor is put forward, and thesystem correction can be improved efficiently after the first iteration. For the large distorted wavefront has strongadaptability especially.