Title :
Electrostatic-Pneumatic Membrane Mirror With Positive or Negative Variable Optical Power
Author :
Moghimi, Mohammad J. ; Dickensheets, David L.
Author_Institution :
Dept. of Electr. & Comput. Eng., Montana State Univ., Bozeman, MT, USA
Abstract :
A microelectromechanical systems (MEMS) deformable mirror is described that uses a novel actuation scheme to increase the optical focus range. In this method, electrostatic-pneumatic actuation is used to achieve a convex surface curvature of the mirror with negative focus, while direct electrostatic actuation creates a concave surface with positive focus. Mirrors have demonstrated 20-μm total stroke with more than 2-kHz bandwidth. The fabricated device consists of two membranes made of the photoset epoxy SU-8. One membrane serves as the deformable mirror and the other one as the pneumatic actuator. The pneumatic membrane also provides a built-in valve for pressure equalization. The principle of operation, fabrication process, and results are presented.
Keywords :
electrostatic actuators; membranes; microactuators; micromirrors; pneumatic actuators; resins; actuation scheme; built-in valve; concave surface; convex surface curvature; direct electrostatic actuation; electrostatic-pneumatic actuation; electrostatic-pneumatic membrane mirror; microelectromechanical systems deformable mirror; negative focus; negative variable optical power; optical focus range; photoset epoxy SU-8; pneumatic actuator; positive focus; positive variable optical power; pressure equalization; size 20 mum; Cavity resonators; Electrostatic actuators; Force; Mirrors; Pneumatic actuators; Valves; MEMS deformable mirror; SU-8; concave mirror; convex mirror; electrostatic-pneumatic actuation;
Journal_Title :
Microelectromechanical Systems, Journal of
DOI :
10.1109/JMEMS.2014.2346758
