  Miniaturized two-dimensional scanning mirror based on microelectromechanical
systems (MEMS) technology has great potential in automotive industry, consumer
electronics, and biomedicine, etc. Due to its high frequency and large angle,
resonant scanning is the mainstream in all MEMS actuation mechanisms, such as
harmonic resonant electromagnetic scanner and parametric resonant electrostatic
scanner. Although electrostatic scanner has the advantages of low power
consumption and IC process compatibility, some shortcomings of parametric
resonance, including double frequency of driver electronics and additional
feedback control or frequency stabilization system, limit its further
application. The symmetry of coplanar electrostatic comb actuator is broken in
this paper, and harmonic resonant electrostatic scanner with excellent
performance is realized. Further, through adopting mechanical filter,
two-dimensional scanning can be achieved through one set of actuators, which
avoids the problem that two sets (each for one dimension) of electrostatic
actuators must be insulated each other through complicated and expensive
processes. A two-dimensional MEMS scanner based on symmetry breaking and
mechanical filter was proposed and demonstrated. Multiple scanning modes can be
achieved through selective control of a set of four identical actuators.
