Wavefront reconstruction of Shack-Hartmann data for a high-resolution pixelated wavefront corrector

Abstract

The subapertures defined by a Shack-Hartmann wave front sensor are highly oversampled when a high-resolution pixelated liquid crystal device (LCD) is used for wave front correction. Wave front reconstruction requires that appropriate phase values be assigned to all LCD pixels within each oversampled subaperture. We have implemented a reconstructor that uses a least squares approximation to calculate the phase values for the subaperture corners based on the Shack-Hartmann data. It then uses a zonal fitting interpolation method to assign phase values to the rest of the LCD pixels without creating discontinuities between the subaperture regions. Experimental results are presented.