DEVELOPMENT OF MICROELECTROMECHANICAL OPTICAL SCANNER

Rockwell is working on the development of a micro-electro-mechanical o ptical scanner based on bimorph microactuators. This scanner is lightw eight, is small, and has superior scanning performance. The scanner is a low-power (<1 W) device that has large scan angles (approximate to 20 deg) acid scan rates in the range of 100 to 2000 Hz. It works for a ll wavelengths and offers the potential for monolithic integration wit h both electronics and optics for on chip signal processing and contro l. The optical scanner consists of two main components-actuator and mi rror-which are fabricated on a silicon cantilever beam. The actuator i s comprised of a bimorph layer covered with two metal layers, which fu nction as top and bottom electrodes. The mirror can be as large as 12 mm(2) in area, is placed at the end of the cantilever beam, and is des igned for maximum optical flatness. The optical efficiency of the devi ce is very high and can exceed 90% on proper metallization of the mirr or area. The scan angle is a function of beam thickness, power efficie ncy of the bimorph, and many other design criteria, through many impro vements in these design parameters, a scan angle greater than 20 deg i s expected to be achieved with high yield. (C) 1997 Society of Photo-O ptical Instrumentation Engineers.