Preliminary results of large-actuator-count MEMS DM development

摘要

Compensating for atmospheric turbulence in meter-class telescopes and for free-space communications can require deformable mirrors (DM) with hundreds of actuators. Advances in high-contrast imaging techniques and increased telescope sizes require DMs mirrors with thousands of actuators [l]-[3]. In response to these needs, Iris AO has been developing a nearly 500-actuator DM and is conducting pathfinding research into 3000-actuator class DMs. This paper begins with an overview of the segmented DM design and describes improvements made to the DM over the prior year in the areas of speed, high-quality dielectric coatings, and snap-in prevention structures. The paper then describes the next-generation PTT489 DM design and fabrication process. Failure modes encountered during fabrication are presented as well as test methods to detect the failure modes. Preliminary yield data are presented for the fabrication process as well. The paper concludes with a view to the future showing pathfinding research into 3000-actuator DMs.