ELECTROSTATIC COMBDRIVE-ACTUATED MICROMIRRORS FOR LASER-BEAM SCANNINGAND POSITIONING

We describe the design and fabrication of surface-micromachined resona nt microscanners that have large scan angles and fast scan speeds, The se scanning micromirrors, which are hundreds of micrometers on a side, are driven by electrostatic-comb actuators and have resonant frequenc ies in the kilohertz range, Fabricated with two or three structural la yers of polysilicon, the scanners are compact, extremely light in weig ht, and potentially very low in cost, Their power consumption is also minimal because the capacitive motors draw very low currents, High-pre cision positioning (0.01 degrees dynamically and 0.038 degrees statica lly) over a large angular range (up to 28 degrees optical angle) makes the micromirrors suitable for a variety of optical applications such as laser scanners and printers, displays, holographic data storage, an d fiber-optic switches, We have demonstrated microscanners of this typ e in bar-code readers, which are important devices with a growing numb er of applications in many industries.