• scanner;
  • MEMS;
  • piezoelectric actuator;
  • ZnO;
  • optical scanning;
  • laser display


A fast and wide deflection silicon-resonant torsional optical scanner driven by a piezoelectric actuator has been developed and patented. The scanner is composed of a 1-mm square mirror and two pairs of torsion beams and arms fabricated using microelectromechanical system (MEMS) processing of a silicon-on-insulator (SOI) wafer. According to calculations, at the same resonant driving frequency, the maximum principal stress of this structure was about one-third smaller than that of the usual structure having one pair of torsion beams. We achieved high frequency scanning of the optical beam with a large angular deflection up to 54° at 38 kHz with a 5 V peak-to-peak applied voltage using the bulk piezoelectric stack actuator, and up to 17° at 38 kHz with a 25 V peak-to-peak voltage using the unimorph actuator of a zinc oxide (ZnO) thin film. These results show that this scanner has the ability to perform the horizontal scanning for high-resolution extended graphics array (XGA) or super extended graphics array (SXGA) laser display. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.