Micromachined Vibratory Diffraction Grating Scanner for Multiwavelength Collinear Laser Scanning

This paper presents an effective method to achieve multiwavelength collinear laser scanning using micromachined vibratory grating scanners, which have the potential to scan at high frequencies without the optical performance degradation resulting from dynamic nonrigid-body deformation. An optical simulation model has been developed to predict the scanning patterns of the vibratory grating scanners. The proposed multiwavelength collinear scanning method was studied both analytically with the optical simulation model and experimentally with a prototype device fabricated by the MUMPS polysilicon surface micromachining process. The experimental results agree very well with the simulation data. The prototype scanner demonstrated collinear scanning of 532 nm (green) and 632.8 nm (red) wavelengths laser beams and achieved an optical scan angle of 12.7 degrees with virtually bow-free scan-line at a resonant frequency of 9.9 kHz when driven by electrostatic comb-drive resonators with 60 V dc bias and 32 V_pp ac voltages