论文部分内容阅读
夏克-哈特曼波前传感器测量畸变波前的探测精度主要取决于光斑质心的测量精度。提出了一种提高光斑质心探测精度的新方法,在优化的探测窗口内使用高阶矩方法计算光斑的质心。首先,在整个子孔径内,通过一阶矩方法获得光斑的近似中心,然后以这个近似中心为中心,包含整个光斑,建立一个矩形窗口,并在该窗口内通过高阶矩方法重新计算光斑的质心。通过该改进的方法,在优化的探测窗口外,噪声的影响基本被消除;在优化的探测窗口内,噪声的影响也因为光斑权值比重的增大而削弱。实验结果证明:与传统方法相比,新方法提高了光斑质心测量的精度、重复性和稳定性。
The Shack-Hartmann wavefront sensor measures the detection accuracy of the distorted wavefront mainly depending on the measurement accuracy of the spot centroid. A new method to improve the detecting accuracy of the centroid of the light spot is proposed. The centroid of the light spot is calculated by using the high moments method in the optimized detection window. Firstly, the approximate center of the light spot is obtained by the first-order moment method in the whole sub-aperture, and then the entire light spot is centered on this approximate center, a rectangular window is established, and the light spot is recalculated by the high-moment method in the window Centroid. Through the improved method, the influence of noise is basically eliminated outside the optimized detection window. In the optimized detection window, the influence of noise is also weakened due to the increase of the weight proportion of the light spot. The experimental results show that compared with the traditional method, the new method improves the accuracy, repeatability and stability of the centroid measurement.