Electromechanical characterization of a new micro programmable blazed grating by laser Doppler vibrometry

The prototype of a new micro programmable blazed grating driven electrostatically was fabricated using a two-layer polysilicon surface micromachining process. And initially, to characterize its electromechanical performances, such as the driving voltage versus displacement relationship, frequency response and step response, the laser Doppler vibrometry was employed. The measured results reveal the pull-in voltage of 110-115 V, resonant frequency of 78 KHz, quality factor of 2.89, adjusting time of 12 μs, and damping ratio of ~0.68 for the achieved grating sample. As a result, the grating functions well electromechanically. As for its optical performances, a number of optical experiments are in progress.