Large aperture MEMS mirror with integrated piezoelectric actuator

MEMS micromirror is playing more important roles in various applications. To increase the detection range and field-ofview (FOV), bigger aperture size with larger rotation angle (θopt⋅D) is always preferred. However, it comes with the cost of worse collimation performance due to larger dynamic deformation. A backside rib support design can be added to the mirror which can reduce dynamic deformation while keeping rotational inertia of moment low. Meanwhile, integrated piezoelectric actuator can be adopted to provide large driving force and to increase the rotation angle. In this paper, we demonstrate a MEMS micromirror actuated by integrated PZT thin film, with a large aperture size of 12mm×18mm and resonant frequency of 1.65 kHz can achieve 4.8° optical angle under 20 Vpp driving voltage. Design rules are deduced from the theoretical analysis to improve the performance of piezoelectric-actuated MEMS mirror.