基于优化探测窗口的光斑质心探测方法  

New method for centroid detecting of focal spot based on optimizing detecting window

作　　者：王薇[1] 陈怀新[2] 

机构地区：[1]淮北煤炭师范学院物理系,安徽淮北235000 [2]四川大学电子信息学院,成都610064

出　　处：《强激光与粒子束》2006年第8期1249-1252,共4页High Power Laser and Particle Beams

基　　金：安徽省科技创新团队项目资助课题(2006KJ003TD)

摘　　要：哈特曼-夏克波前传感器进行波前探测时,用子孔径光斑强度的一阶矩来计算光斑质心位置,子孔径窗口作为探测窗口,但探测时子孔径窗口内噪声对一阶矩有很大的影响,会使质心探测精度产生很大的误差。因此在计算质心位置时探测窗口的选取对探测精度有重要影响,必须选取合适的探测窗口来提高光斑质心探测精度。为此,在传统算法的基础上提出优化探测窗口的方法来提高质心探测精度,仿真和实验结果表明新方法提高了质心探测的精度,未经处理的高噪声恢复波前的波前残差峰谷值是2.851 4λ,均方根值是0.606 3λ,优化探测窗口后波前残差的峰谷值是1.636 2λ,均方根值是0.367 1λ,重构误差减小了40%。证明了算法的可行性和稳定性。Detecting and calculating accuracy of centroid of focal spot affects the detecting accuracy of Hartmann-Shack wavefront sensor. Noise will reduce the detecting accuracy when the whole sub-aperture is used as the detecting window. The influence of window selection on centroid detection error is great. In this paper, the method of optimizing detecting window based on traditional algorithm is proposed in order to improve the detection accuracy. Computer simulation indicates that the detection error can be decreased. Also, an optical system for distorted wavefront measurement is built with array Fresnel zone plates as the wavefront sensor. The experimental results show the accuracy of centroid detection is improved. The rms value of the error for recon- struction wavefront with high noise can be reduced from 0. 606 3λ to 0. 367 1λ with 40% decrement. In addition, the effectiveness and stabilization of the new method is proved.

关 键 词：Hartmann—Shack波前传感器 质心探测 优化探测窗口 探测精度 阵列菲涅耳波带片 

分 类 号：O438[机械工程—光学工程]