Error propagation: a comparison of Shack–Hartmann and curvature sensors

Aglaé N. Kellerer, Albrecht M. Kellerer
2011 Optical Society of America. Journal A: Optics, Image Science, and Vision  
Phase estimates in adaptive-optics systems are computed by use of wavefront sensors such as Shack-Hartmann or curvature sensors. In either case the standard error of the phase estimates is proportional to the standard error of the measurements; but the error-propagation factors are different. We calculate the ratio of these factors for curvature and Shack-Hartmann sensors in dependence on the number of sensors, n, on a circular aperture. If the sensor spacing is kept constant and the pupil is
more » ... larged, the ratio increases as n^0.4. When more sensing elements are accommodated on the same aperture, it increases even faster, viz. proportional to n^0.8. With large numbers of sensing elements this increase can limit the applicability of curvature sensors.
doi:10.1364/josaa.28.000801 pmid:21532691 fatcat:zyplo26uabh3rlqmslvdlj6iim