Design and vibration analysis of a piezoelectric-actuated MEMS scanning mirror and its application to laser projection

This study presents the design and analysis of a two-axis scanner driven by lead-zirconate-titanate (PZT) ceramic. The proposed device consists of a silicon-based MEMS scanning mirror and a bulk-type piezoelectric actuator. The MEMS process involves three masks. The experimental results showed that the fast and slow frequencies at resonance are 29.6 kHz and 4.8 kHz, respectively. For the fast scan, the scanning angle is 46.9 degrees at a driving voltage of 10 V. For the slow scan, the scanning angle is 22.6 degrees at a driving voltage of 20 V. A multi-DOF vibration model was developed to analyze the scanning characteristics of the device. The numerical simulations, including the resonance frequency, scanning angle and the mode coupling phenomenon, were validated with the experimental observations. This study also develops a laser projection module integrated with the scanning device. The module can receive a video content with a resolution of 720 p and project a 16:9 image that is 19 inches in diagonal at a projection distance of 600 mm.