Shack-Hartmann wavefront sensing with extended sources

Abstract

Shack-Hartmann wavefront sensor is widely used for the measurement of phase perturbations induced by turbulence. Such a wavefront sensor relies on the measurement of the image displacements in the lenslet array focal plane. Different algorithms can be used to estimate this displacement. This paper is dedicated to the analysis and comparison of their performances. Special attention will be paid to correlation techniques which are well suited to extended sources.