High speed laser scanning using MEMS driven in-plane vibratory grating: Design, modeling and fabrication

In this paper, we report a design, modeling and fabrication of a microelectromechanical system (MEMS) based in-plane vibratory sub-wavelength diffraction grating scanner for high optical efficiency, high speed laser scanning applications. This paper demonstrates that with careful design, optical efficiency of more than 75% is experimentally achievable with a simple gold-coated binary sub-wavelength grating. High frequency scanning of 55.01 kHz with an optical scan angle of 5.2° is achievable even when operated in air. The device demonstrated has a 1 mm diameter grating. Through consideration of the mass of the suspension springs, stress alleviation beams and fabrication imperfections, a theoretical model is proposed which can estimate the dynamic performance close to the actual operating condition.