MEMS 3D optical mirror/scanner

This paper presents a novel MEMS optical mirror based on a proprietary fabrication process. The mirror is fabricated with single crystal silicon and has hexagonal reflective surface 600 μm across, with a measured surface roughness is less than 20 angstroms RMS and a radius of curvature of greater than 5 meters. The device has a full 360° of Z rotation at up to 3° (∼1° controllable) of out of X-Y plane tilt angle depending the design parameters. This mirror has no perforation holes on the reflective surface and no stiction problems during fabrication or operation. The addition of lateral comb drive actuators gives the mirror up to 4 μm X and Y in-plane movement. The control of X and Y translation is totally independent and free of movement interference. Due to all electrostatic actuation, the device has lower power consumption, with a designed driving voltage of less than 120 volts. Simulation results, including modal analysis, are included.