We explore two methods of quantifying and correcting non-common path aberrations (NCPA) both in simulation and on an experimental bench. The first method, called Focal Plane Sharpening (FPS), utilizes an optimization algorithm to maximize the peak intensity of the PSF by varying actuator patterns on a deformable mirror (DM). The second method employs the technique of Phase Diversity (PD) to estimate NCPA by use of PSF images in and out of the focal plane. The experimental tests use a 52 actuator ALPAO DM and 1000 actuator MEMS DM to provide an offset for NCPA correction. Each method shows to be successful in simulation, however FPS is the only method used successfully on an experimental bench; although work is on-going to successfully demonstrate PD. Our aim is to use one or both methods to determine the best approach to NCPA calibration on the MOAO system RAVEN, and extend this calibration method to future systems such as TMT's NFIRAOS.

Date Published: 21 July 2014
PDF: 13 pages
Proc. SPIE 9148, Adaptive Optics Systems IV, 914857 (21 July 2014); doi: 10.1117/12.2055198

Published in SPIE Proceedings Vol. 9148:
Adaptive Optics Systems IV
Enrico Marchetti; Laird M. Close; Jean-Pierre Véran, Editor(s)