利用动态跟踪原理进行质心计算的新方法

A New Centroid Computation Method Using Dynamic Tracking

分析 H- S(Hartm ann- Shack)波前传感器在扩展动态范围及抑止噪声方面存在的不足 ,提出了根据大气湍流的时间特性确定在一次采样时间间隔内质心移动的变化范围 ,对质心进行连续动态跟踪测量的新方法 .该方法在大气扰动较强时 ,可以扩展波前传感器动态范围 ,有效地降低 CCD读出噪声和散弹噪声对质心探测精度的影响 。

Disadvantages of the H S (Hartmann Shack) wavefront sensor in expanding the dynamic range and restraining noise are analyzed. Based on the temporal characteristics of atmosphere turbulence and through determining the scope of change of centroid motion between two adjacent sample periods, a new dynamic track centroid method of H S wavefront sensor is proposed. Using this method, the dynamic range of wavefront sensor can be expanded when atmosphere turbulence is strong. The effect of CCD readout noise and shot noise can be reduced efficiently. The analytical demonstration and simulation results of dynamic centroid computational method are given.