Electrostatically Driven Large Aperture Micro-Mirror Actuator Assemblies for High Fill-Factor, Agile Optical Phase Arrays
AIR FORCE INSTITUTE OF TECHNOLOGY WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT
Pagination or Media Count:
Aircraft laser beamsteering is accomplished using a single gimbaled mirror housed inside a turret, which protrudes from the fuselage and causes unwanted turbulence, vibrations, and weight. The Air Force is currently investigating the use of microelectromechanical systems MEMS micro-mirror arrays to replace aircraft beamsteering technology. MEMS micro-mirror arrays provide a unique solution to address these issues. Unfortunately, current MEMS micro-mirror technology cannot meet all the beamsteering requirements in a single assembly. These include high fill-factor, large aperture, 25 degrees of out-of-plane deflection, 4-axis tilt, and actuation speeds below 1 ms. In this research, a novel MEMS actuation scheme to address all these requirements using electrostatically driven bimorph cantilever beams was designed, modeled, fabricated, and characterized. Modeling results show a linear relationship between the number of cantilever beams and maximum deflection. Characterization of fabricated micro-mirror assemblies supports the modeling for individual actuators as well as for micro-mirror platform assemblies. Fabricated devices reached vertical deflections greater than 170 micrometer with pull-in voltages of 20 V and an optical range of 16 degrees. These large deflections, low pull-in voltage, and reasonable optical range shown in this research demonstrate the feasibility of using MEMS micro-mirror arrays to address aircraft beamsteering issues.
- Lasers and Masers
- Particle Accelerators