Motion Monitoring of MEMS Actuator with Electromagnetic Induction

SUMMARY Previously, we have reported an electromagnetically driven two-axis tilting MEMS mirror, a two-axis tilting grating, and a three-axis movable MEMS mirror (two-axis tilting and one-axis vibration). These devices can be easily actuated by the electromagnetic force induced by a magnetic potential gradient between planar coils and the magnet. However, this open loop system cannot realize precise motion control because of the characteristic deviation of each device, aging deterioration, and thermal behavior. This report describes motion monitoring of MEMS actuators with electromagnetic induction for precise motion control. The theory of motion sensing that we have constructed is shown to agree approximately with experimental results.