基于阈值式小波变换的波前重构算法

摘要

针对传统的波前重构器计算效率低、稳态误差大的问题,提出了阈值式波基多分辨力波前重构算法,采用4维波基作为标准正交基,将波前相位畸变投射到4维波基上,使伪逆矩阵变为稀疏矩阵,有效地减少了计算量,并采用阈值法去除波前重构矩阵算子中对精度影响较小的高分辨力波基系数,进一步增加了矩阵的稀疏程度,提高了运算效率,并与传统的最小二乘法、Zernike模式法和迭代法进行了计算量和均方根误差的比较,仿真结果表明该算法无论在计算速度和收敛精度上均优于其它算法.%A thresholding wavelet multiresolution wavefront reconstruction algorithm is proposed in view of low calculating efficiency and large stable state error of conventional wavefront reconstructors. The wavefront phase distortion is projected to wavelet basis, which makes the pseudo-inverse matrix become sparse matrix and reduces the calculation. Meanwhile, threshold is chosen to remove the high resolution wavelet-based coefficients which have little effect on calculation precision, improving operation efficiency. The algorithm is compared with least square, Zernike modal and iterative methods, and the simulation results show that this algorithm is superior in computing speed and convergence precision.