Electromagnetically driven 4×4 micromirror arrays based on FPCB

This paper proposes an electromagnetic-driven micromirror array based on a flexible printed circuit board (FPCB). The design mainly consists of three parts: a silicon mirror, an FPCB driving structure, and a permanent magnet. The silicon mirror is attached to the FPCB driving structure. By adjusting the current magnitude and direction in the coil of the FPCB, the magnitude and direction of the magnetic force between the coil and the permanent magnet can be changed, which induces mechanical deformation of the driving structure and thus realizes the deflection and translation of the mirror. Experimental results show that the fabricated 4×4 micromirror array has a unit static resistance of approximately 9Ω, a resonant frequency of 138Hz, and a fill factor of 85.5%. Under a driving voltage of ±2.5V and an operating current of 200mA, each unit can achieve an optical deflection angle of more than ±28°. This study verifies the feasibility of using FPCB as the driving structure.