Varifocal Micromirror Integrated With Comb-Drive Scanner on Silicon-on-Insulator Wafer

Abstract

We present a varifocal scanning micromirror fabricated from a silicon-on-insulator wafer. The varifocal scanning micromirror consists of a varifocal mirror with a rotational scanning function. The scanner and varifocal mirror are driven by comb and parallel-plate electrostatic actuators, respectively. The mirror rotates 5.5 • at 45 V in static mode. The curvature of the varifocal mirror is changed from −4 m −1 (−128-mm focal length) to +5 m −1 (+93-mm focal length) by applying a voltage from 0 to 50 V. It is confirmed that the lateral position and spot size of the reflected laser beam from the varifocal scanning micromirror are changed simultaneously. Moreover, confocal sensing is demonstrated using a fiber-optic system with the proposed mirror.[2011-0307.R1]Index Terms-Comb-drive actuator, confocal microscope, electrostatic actuator, micromirror, scanner, silicon on insulator (SOI), varifocal mirror.

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MEMS 3-D Scan Mirror With SU-8 Membrane and Flexures for High NA Microscopy

“…Another gimbal-less mirror capable of lateral scanning and variable surface curvature for focus control is based on electro-thermal bimorph actuation [26]. A varifocal mirror attached to a single axis scanning platform has also been investigated [27, 28].…”

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