Double stage FPCB scanning micromirror for laser pattern generation

This paper presents a double stage FPCB (Flexible Printed Circuit Board) electrostatic parallel plate (DSFP) micromirror. It is designed and fabricated base on mature commercial FPCB processes with low cost. The DSFP micromirror includes a FPCB moving electrode in the middle, two identical FR4 PCB fixed electrodes on both sides and a silicon mirror plate with aluminum coating. Compare with conventional MEMS micromirrors, it has much lower cost, shorter fabrication cycle and higher mirror surface quality. The performances of DSFP micromirror are modeled by Finite Element Analysis (FEA) software ANSYS. Prototypes are fabricated and tested. It can reach 3.25° average rotation angle with 100 V sinusoidal driving at 117 Hz resonance.