241单元变形镜结构参数设计及性能仿真

Structural Parameter Design and Performance Simulation of 241-Element Deformable Mirror

利用多物理场软件COMSOL,建立241单元变形镜模型,计算得到变形镜驱动器影响函数数据。利用基于子孔径斜率法的241单元自适应光学系统光学像差校正程序,以3~60项泽尼克多项式拟合残差的均方根值为目标,分析了变形镜结构参数对系统校正能力的影响,确定了最佳参数值,计算得到最佳参数下的变形镜耦合量为11%。在241单元自适应光学系统中哈特曼传感器与变形镜之间存在不同平移和旋转误差的条件下,分析了系统对泽尼克多项式拟合能力的影响。结果表明,平移量和旋转量分别不能超过3mm和6°。

The 241-element deformable mirror model is built using COMSOL Multiphysics, and the influence function data of the driver of the deformable mirror are acquired by calculation. Based on the sub-aperture slope method, a procedure is compiled, by which the optical aberration of the 241-element adaptive optics system is corrected. By taking the root mean square value of the residual fitting error of a 3-60 order Zernike polynomial, the optimal parameter is determined by analyzing the influence of the structural parameters of the deformable mirror on the correction capability. Under this optimal parameter, the coupling factor of the deformable mirror is calculated as 11%. The influence of the system on the fitting ability of the Zernike polynomial is analyzed considering that there exist different translation and rotation errors between the Hartmann sensor and the deformable mirror in the 241-element adaptive optics system. The results show that the translation and rotation errors are not greater than 3 mm and 6°, respectively.