
第19卷第12期 2011年12月
1004-924X(2011)12-301609
文章编号
光学精密工程
Optics and Precision Engineering
Vol. 19No.12
Dec, 2011
人眼像差探测哈特曼波前传感器的质心优化
钮赛赛",沈建新1·,梁春",张运海2
(1.南京航空航天大学机电学院,江苏南京210016; 2.苏州六六视党科技股份有限公司,江苏苏州215005)
摘要:为提高自适应光学系统中Hartmann-Shack波前传感器的动态测量范围和测量精度,对由CCD采集的波前光斑图进行了质心探测研究。介绍了波前传感器的工作原理,根据127单元传感器的结构特征和实际人眼光斑图的畸变特点,提出了一种动态定位光斑区域、动态分割区域内部阀值以及锁定最优探测窗口的自适应光斑质心探测方法,讨论了该方法中阀值等级选取对人眼光斑图质心探测的影响,并通过仿真和实验分析了算法的质心探测精度和算法对噪声影响的鲁棒性。实验结果表明,光斑区域内选取阔值等级为总等级数的(50士3)%时最合适;与其他方法相比,自适应质心探测方法的探测误差减小了60%以上;将该探测方法运用至自适应光学视网膜成像系统的波前传感器中,可将人眼像差 RMS值从0.728入闭环校正到0.081入(入=785nm),达到衔射极限,并获得视网膜图像。本方法针对光班特征选择不同
实验参数,弥补了传统算法的局限性,基本满足了人眼像差测量的可行性和实用性。关键调:自适应光学;Hartmann-Shack波前传感器;质心探测;人眼像差
中图分类号:TP212.14;TP391
文献标识码:A
doi:10. 3788/OPE, 20111912. 3016
Centroid optimization of Hartmann-Shack wave-front sensor
forhumaneyeaberrationdetection
NIU Sai-sai', SHEN Jian-xin'', LIANG Chun', ZHANG Yun-hai
(l.CollegeofMechanicalandElectricalEngineering,NanjingUniversityof
AeronauticsandAstronautics,Nanjing210016,China;
2.Suzhou 66Vision TechnologyCo.Ltd.,Suzhou215005,China)
Correspondingauthor,E-mail:cadatc@nuaa.edu.cn
Abstract: In order to improve the dynamic measurement range and measurement accuracy of the Hart mann-Shack Wavefront Sensor (HSWS) in an adaptive optics system, the centroid detection for a wavefront spot pattern collected by a CCD is researched. The principle of HSWS is introduced and an adaptive centroid detection method by dynamic positioning spot region, dynamic segmenting threshold level and locking optimal detection window is presented according to the structure features of HSWS with 127 units and the distortion characteristics of actual human eye spot pattern. The effects of threshold level selection on human eye spot centriod detection are discussed and the centroid detection accuracy and noise robustness of the method are analyzed through simulation and experiments. Exper-
收稿日期:2011-05-03;修订日期:2011-05-26.
基金项目:国家863高技术研究发展计划资助项目(No,2006AA020804);2010年江苏省普通高校研究生科研创新
计划资助项目(No.CX10B_107Z)