Further techniques for LGS tilt recovery: the perspective and the predictive a

摘要

Abstract: The recovery of the absolute tip-tilt of a laser guide star (LGS) is a crucial one in the laser assisted adaptive optics programs, especially in the visible wavelengths where the natural sky coverage is poor. A number of techniques have been proposed to achieve this goal: the multicolor LGS by Foy, the use of auxiliary telescopes, the use of auxiliary laser projector, the use of the propagation delay, by our group. In this paper two more possible solutions are presented. These techniques are partly speculative or require a strong technological development and are here reported in the hope that the dissemination of new and unconventional ideas on this problem will lead to some efficient solution. !12