Closed-loop AO Demonstration of MEMS SLM with Piston, Tip, and Tilt Control

A MEMS SLM with an array of 64 x 64 pixels, each 120 mu m x 120 mu m in size, with 98% fill-factor, has been developed. Each reflector in the array is capable of 5 mu m of stroke, and +/- 4 degrees tip and tilt. From a prototype array, 14 contiguous pixels have been independently wired-out to off-chip drive electronics. These 14 pixels have been demonstrated to be effective in an off-the-shelf AO system (with requisite modifications to suit the SLM). For a low-order static aberration, the measured Strehl ratio has been improved from 0.069 to 0.861, a factor of 12 improvement.