COMPARISON OF CURVATURE-BASED AND SHACK-HARTMANN-BASED ADAPTIVE OPTICS FOR THE GEMINI TELESCOPE

We present the results of independent numerical simulations of adaptiv e optics systems for 8-m astronomical telescopes that use both Shack-H artmann and wave-front curvature sensors. Four differents codes provid ed consistency checks and redundancy. All four simulate a complete sys tem and model noise and servo-lag effects. A common atmospheric turbul ence generator was used for consistency. We present the main character istics of the codes, and we report the system performance in term of S trehl ratio and full width at half-maximum versus the magnitude of the (on-axis) guide star. We show that a Shack-Hartmann plus stacked actu ator mirror system with 10 x 10 subapertures or a curvature plus bimor ph mirror system with 56 subapertures yields a 50% Strehl ratio at 1.6 mu m for a m(R) = 167 magnitude star, with almost equivalent performa nce at both brighter and dimmer light levels. (C) 1997 Optical Society of America.