Piezoelectric Moonie‐type Resonant Microactuator

SUMMARY This paper reports a piezoelectric in‐plane resonant actuator for a speckle dissolution device used in a laser‐type projector. An optical diffuser is oscillated by this actuator to reduce the coherency of a scanned laser beam. A PZT unimorph actuator combined with a Moonie‐type displacement amplifier and a resonant structure was used to obtain a large displacement. The L18 design of experiment method was used for the optimal design. Both 1‐axis and 2‐axis actuators were designed and fabricated. The maximum displacement as high as 239.5 μm at a resonance frequency of 325.2 Hz was obtained for the 1‐axis actuator, and the maximum displacements of 109.5 μm and 67 μm for l.5 Hz for both x‐ and y‐direction at resonance frequencies of 621.5 Hz and 288.5 Hz were obtained for the 2‐axis actuator (10 V). The actuator was also tested with a dummy optical diffuser to evaluate the influence of the additional mass.