High Surface Accuracy Resonant Varifocal Mirror

Abstract

Electrostatically actuated resonant varifocal mirrors were developed by bonding a silicon-on-insulator wafer and a glass wafer. Three different types of supporting fringes for the mirrors were tested to study the mirror's surface profiles by using the optical interference images. The surface profile deviation from the ideal parabolic shape was supported to 70 nm or less when the mirror's supporting fringe was made to be mechanically compliant.