Synchronized laser scanning of multiple beams by MEMS gratings integrated with resonant frequency fine tuning mechanisms

This paper presents an effective method to achieve synchronized laser scanning of multiple beams by using MEMS diffraction gratings with their resonant frequency fine tuning mechanisms. Multiple gratings are actuated in-plane by a common electrostatic comb-driven resonator and their resonant frequencies can be fine-tuned to compensate the micromachining process errors. Continuous and reversible resonant frequency tuning was achieved. The resonant frequency of one diffraction grating gradually dropped from 19870 Hz to 19588 Hz with its tuning voltages increased from 0V to 5V. Finally, synchronized laser scanning of multiple beams was demonstrated using stroboscopic method.