摘要
自适应光学系统中采用CCD作为哈特曼波前传感器的光斑质心位置探测器时,由于光斑的高斯宽度较小会带来大采样误差。针对该问题,本文详细分析了采样误差形成的原因,建立了采样误差、位移敏感度和开环动态范围与光斑高斯宽度、光斑位置以及子孔径大小的数学模型,提出标定时光斑质心的最佳位置是子孔径中心四像素的中心。因为在该位置处,CCD的质心探测具有闭环时采样误差为0,位移敏感度最大,且开环时动态范围最大的特点,为哈特曼波前传感器的标定方法的研究提供了理论依据。
The Gauss width of focal spot which is too small results in the sampling error while using CCD as the centroid detecting device of Shack-Hartmann Wavefront Sensor （SHWS） in Adaptive Optics （AO） system. In order to solve the problem of sampling error, the reason of sampling error of CCD is analyzed in detail. The math model of sampling error, displacement sensitivity and open loop dynamic range are established. The results show that the optimal position during sensor calibration is the center of the four pixels of sub-aperture, where centroid detection possesses that sampling error is 0 and the displacement sensitivity and the open loop dynamic range are maximum as well. It provides theoretical basis for research of SHWS calibration method in AO system.
出处
《光电工程》
CAS
CSCD
北大核心
2009年第4期22-26,69,共6页
Opto-Electronic Engineering
基金
中科院研究生科学与社会实践(创新研究类)资助课题(1191300104)
关键词
自适应光学
哈特曼波前传感器
采样误差
位移敏感度
adaptive optics
Shack-Hartmann wavefront sensor
sampling error
displacement sensitivity
