It is possible to create custom laser guidestar (LGS) asterisms from a single beam by using a deformable mirror to pattern the phase of the outgoing laser guidestar beam. This avoids the need for multiple laser launch assemblies, and in principle would allow one to position the multiple LGS spots in any desired arrangement around the science target, as well as dynamically rotate the LGS pattern on-sky and control the distribution of intensity in each spot. Simulations and laboratory experiments indicate that a PTT111 and PTT489 IrisAO MEMS deformable mirror and a Hamamatsu X8267 spatial light modulator may have applications for creating small LGS asterisms for biological imaging with adaptive optics. For astronomy applications, the phase values required to produce the “3+1” laser guidestar asterism of Keck’s Next Generation AO system is also investigated.

Date Published: 7 August 2014
PDF: 12 pages
Proc. SPIE 9148, Adaptive Optics Systems IV, 91483N (7 August 2014); doi: 10.1117/12.2057139

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