Push-pull deformable mirror: Characterization and closed loop operations

In this paper we describe the performances of a "push-pull" deformable minor (DM) which has the advantage of having a mirror membrane that can be attracted either from the back, as conventional electrostatic minors, or from the front. This technology has several advantages such as: doubled maximum defonnation, a better accuracy in phase mode reproduction, and bidirectional defonnation that allows closed loop operations without biasing. The key idea, when developing this push-pull defonnable mirror, was to have a good compromise benveen perfomiances and practical applicability for series production. An analysis of the constraints/practical limitations is described using simulations and laboratory tests. Following these results, we foresee the benefits of inserting the push-pull DM (Saturn. Adaptica Sri) in practical applications such as ophthalmology and microscopy. © 2012 SPIE.