Design of Butterfly Plate Piezoelectric Actuator with Dual Driving Electrodes for MEMS Micro-Mirror

This study presents a novel butterfly-plate piezoelectric actuator to drive MEMS micro-mirror with decent scanning angle and frequency at low voltage. The micro-mirror is driven by four butterfly-plate actuators around the mirror plate. Merits of this study are, (1) butterfly-plate actuators with dual driving electrodes: butterfly-plate actuator has larger PZT area (than cantilever actuator) to contribute higher driving force, and the round corner on butterfly-plate is to remove the structure with larger bending caused by residual stress. The dual driving electrodes is exploited to further enhance the output displacement. (2) boundary of actuator: the proposed boundary condition of actuators could reduce the constraint of butterfly-plate to enhance its output displacement. Measurements demonstrate the proposed micro-mirror has 38-degree scanning angle with scanning frequency of 25.5 kHz when driving at 12 V
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