Laser guided adaptive optics for high-resolution astronomy

Summary form only given. Adaptive optics remove distortions caused by atmospheric turbulence by making corrections to the incoming wave front using one or more bright points of light in the area being observed as references. The use of multi-conjugate adaptive optics with multiple reference points can provide three-dimensional imaging of the regional turbulence. The required reference points can be artificial light sources created by shooting multiple lasers at the sky to excite mesospheric sodium atoms located 90 kilometers above the ground. Laser systems for adaptive optics need to be precisely tuned to the sodium D/sub 2/ transition (589 nm) and are unusually powerful (7-24 W) for lasers at this wavelength. The current state-of-the-art laser guide star (LGS) systems consist of either complex sum-frequency generation lasers or multiple-laser-pumped dye lasers based on the technology developed for the AVLIS Program at LLNL.