A 50 kHz Micromachined Electrostatic Driven Vibratory Grating Laser Scanner

A 50 kHz micromachined electrostatic driven vibratory grating laser scanner has been successfully developed for high-speed laser scanning applications. Unlike the conventional grating platform having uniform thickness across the entire diffraction surface, the grating platform in this study is thinned and reinforced by a circular frame, which is used to reduce its rotational inertia and keep its rigidity. The scanner is fabricated using a simple silicon-oninsulator (SOI) technology based micromachining process with only 4 photo masks used. This paper presents the design, simulation, fabrication process and experimental measurement results of the high-speed vibratory grating scanner. The prototype scanner with a 1 mm diameter diffraction grating is capable of scanning at 50.192 kHz with and optical scan angle of 14.1° when illuminated with a 635 nm wavelength incident laser beam.