Abstract 145

Submitted by Enguerran DELAVAQUERIE

Authors

E. Delavaquerie, F. Cassaing

Affiliations

ONERA

Abstract

One of the major issues for large telescopes is the phasing of their segmented primary mirror. An optical cophasing sensor is mandatory to achieve the ultimate resolution of the telescope. In this talk, we will present focal plane wavefront sensing (WFS) techniques that allow to perform piston measurements between the segments. First, we will present results from a new simple algorithm that retrieves phase step information from a Shack Hartmann WFS whose lenslets overlap the intersections of two segments. Then we will extrapolate this pairwise measurement to a larger group of segments, with Phase Diversity.