PROBLEM TO BE SOLVED: To provide a structure capable of suppressing pull-in even when the drive voltage is increased for increasing the movable amount, in an actuator including a comb-tooth electrode or a variable shape mirror using the same.SOLUTION: An electrostatic comb-tooth actuator 101 has a plurality of fixed comb-tooth electrodes 108 extending from a support member 105, an elastic member 104 connecting a movable member 103 and the support member 105, and a plurality of movable comb-tooth electrodes 106 extending from the movable member 103 substantially in parallel with the fixed comb-tooth electrodes 108, and meshing therewith at intervals. A structure for applying individual potentials, respectively, to a portion of the support member 105 facing the outermost movable comb-tooth electrode in the arrangement direction of the plurality of movable comb-tooth electrodes 106, and a portion of the support member 105 from which the fixed comb-tooth electrodes extend is provided.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2016,JPO&INPIT【課題】櫛歯電極を含むアクチュエータやそれを用いる可変形状ミラーなどにおいて、可動量を大きくするために駆動電圧を大きくするときにもプルインが抑制できる構造を提供する。【解決手段】静電櫛歯アクチュエータ101は、支持部材105から延出する複数の固定櫛歯電極108と、可動部材103と支持部材105とを繋ぐ弾性部材104と、可動部材103から固定櫛歯電極108と略平行に延出しこれと間隙を隔てて噛み合う複数の可動櫛歯電極106を有する。複数の可動櫛歯電極106が配置されている方向において最外の可動櫛歯電極に対向する支持部材105の部分と固定櫛歯電極が延出する支持部材105の部分それぞれに個別電位を印加するための構造が設けられている。【選択図】図1
