The New Adaptive Optics Module for Interferometry (NAOMI) is the future low order Adaptive optics system to be developed for and installed at the ESO 1.8 m Auxiliary Telescopes (ATs). The four ATs are designed for interferometry which they are essentially dedicated for. The project goal is to equip the telescopes with a low-order Shack-Hartmann system operating in the visible in place of the current tip-tilt correction. The deformable mirror (DM) for NAOMI is rotating with the AT azimuth axis whereas the wavefront sensor (WFS), which signals are used to control the DM, has a fixed position in the telescope basement. It is not co-rotating with the DM. The result is that the projection of the actuator pattern is rotating with respect to the WFS when the telescope is tracking an object on sky. In order to avoid the use of an optical de-rotator we developed an algorithm to de-rotate the commands to the DM in software. This paper outlines the concept of the software de-rotation as well as the performance obtained from end-to-end simulations.

Date Published: 21 July 2014
PDF: 12 pages
Proc. SPIE 9148, Adaptive Optics Systems IV, 91484A (21 July 2014); doi: 10.1117/12.2055072

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