Micromachined in-plane vibrating diffraction grating laser scanner

In this letter, we present a novel micromachined vibrating diffraction-grating laser scanner that utilizes in-plane angular vibration of a planar diffraction grating causing the diffracted laser beam to scan. The proposed micromachined diffraction-grating laser scanner can operate with low voltage and has the potential to scan at high frequencies without the optical performance degradation due to dynamic nonrigid-body deformation, which is prevalent in conventional high-speed out-of-plane torsional micromirror scanners. A prototype grating scanner has been developed using micromachining technology to demonstrate this new microscanner principle. The tested device is capable of scanning an optical angle of 15.9° with virtually bow-free scan-line at a resonant frequency of 8.34 kHz for a 635-nm wavelength incident laser beam, electrostatically driven by 15-V dc bias and 15-V ac voltages.