基于矩形象限法的光斑质心定位算法研究

Localization of Facular Centroid Based on the Rectangular Quadrant Algorithm

激光大气传输会发生波前畸变,为了探测波前,采用哈特曼夏克(H-S)传感器来获取波前信息,采用算法对成像光斑进行质心定位,进而可以达到波前检测的目的。通过质心法对哈特曼夏克波前传感器得到的光斑图像进行处理,进而确定出其质心的位置和算法所需的时间。采用改进的象限法,通过检测光斑的边缘位置,进而确定出一个能将光斑圈住的矩形的大小和位置。根据几何学关系,针对不同位置的光斑采用不同的方法确定质心,进而可以得到质心的位置。通过与质心法对比仿真,结果显示两种算法的质心位置坐标很接近,算法的速度也很接近。

Laser suffers wavefront distortion in atmospheric transmission. In order to detect the wavefront, we use the Hartmann-Shack （H-S） wavefront sensor to obtain the information of wavefront and locate the centroid of facula by the centroid algorithm. In this way, we can achieve wavefront detection. We put forward the algorithm of rectangular quadrant and obtain the location of centroid by experiment, thereby using the rectangle to enclose the facula. The rectangle can be divided into four parts by axes. The sum of gray values in each part can be determined. According to the geometrical relationship, different formulas are used to determine the centroid for rectangles at different positions. By comparison with the centroid algorithm, it is found that the positions of centroid derived from two algorithms are nearly the same and the speeds of two algorithms are also nearly equal.