Micromirror actuator

Abstract

Disclosed is a micromirror actuator with the degrees of freedom of two axes operated by an electrostatic force. The micromirror actuator comprises: a substrate provided with an insulating layer formed thereon; two lower columns spaced from each other by a designated distance, and formed on the insulating layer; a first torsion bar extending over upper surfaces of the lower columns; a second torsion bar formed so that the first and second torsion bars are orthogonal to each other; four electrodes, each disposed in four areas formed by the orthogonal crossing of the first and second torsion bars, formed on the insulating layer; two upper columns formed on an upper surface of the second torsion bar so that upper surfaces of the upper columns are located at higher positions than upper surfaces of the electrodes; and a micromirror located on the upper surfaces of the upper columns so that the micromirror is supported by the upper columns. In the micromirror actuator, the micromirror is elevated to a desired height by means of two upper columns, and the dimensions of its structure are reduced by locating torsion bars under the micromirror. Further, the micromirror actuator allows the micromirror to be selectively tilted centering on two torsion bars depending on electrodes to which voltage is applied, thus being used as a three-dimensional optical switch.

Dependencies are inferred from the claim text.