扫描式眼波前像差系统的夏克–哈特曼波前传感器质心探测研究  

Centroid detection of Shack-Hartmann wavefront sensor in scanning ocular wavefront aberration measurement system

作　　者：周文豪 刘佩杰 尚昆 曾茜 郭世俊 周传清 ZHOU Wenhao;LIU Peijie;SHANG Kun;ZENG Xi;GUO Shijun;ZHOU Chuanqing(School of Health Science and Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;College of Medical Instruments,Shanghai University of Medicine and Health Sciences,Shanghai 201318,China)

机构地区：[1]上海理工大学健康科学与工程学院,上海200093 [2]上海理工大学光电信息与计算机工程学院,上海200093 [3]上海健康医学院医疗器械学院,上海200237

出　　处：《光学仪器》2024年第4期14-21,共8页Optical Instruments

基　　金：国家自然科学基金(61875123)。

摘　　要：针对扫描式眼波前像差系统难以消除所有视角方向系统噪声的问题,提出了一种在大噪声条件下准确定位光斑阵列的质心并进行波前重建的方法。首先使用中值滤波与数学形态学方法对图像进行全局处理;接着使用改进的最大间类方差方法选取每个子孔径的阈值;然后通过Suzuki轮廓跟踪算法确定需要计算的光斑窗口;最后结合所提出的中值面积法精确定位光斑质心。通过对比发现,传统方法对此类大噪声条件下的真实光斑已无法进行判别,而新提出的方法可以进行正确识别,重建波前的PV值误差小于0.015λ,RMS小于0.001λ,说明该方法的准确度与稳定性明显优于传统方法。In response to the challenges of eliminating the system noises from different viewing directions in a scanning ocular wavefront measurement system,this paper proposes a method to accurately locate the centroids of the spot array of Shack-Hartmann wavefront sensor and reconstruct the wavefront under high noise conditions.At first,the spot array images were globally processed using median filtering and mathematical morphology methods.Secondly,an improved maximum inter-class variance method was employed to determine the threshold for each subaperture.The Suzuki contour tracing algorithm was then utilized to identify the spot windows within which the centroids were computed.Finally,the proposed method combining the median area method precisely determined the centroid of the spots.A comparative analysis revealed that traditional methods failed to discriminate real spots under such high-noise conditions,whereas the proposed method could correctly identify them.The wavefront reconstruction errors,evaluated with PV and RMS values were less than 0.015λand 0.001λrespectively,indicating that the accuracy and stability of the proposed method significantly outperformed traditional approaches.

关 键 词：波前传感器 图像处理 质心定位 波前重建 

分 类 号：TH741[机械工程—光学工程]