A spatial light modulator has: a support substrate that has an electrode layer; and a movable thin film that has at least an electrode layer, and that is opposingly placed above the support substrate with being separated by a predetermined gap distance in a manner that the movable thin film is flexurally deformable toward the support substrate, and in which a predetermined driving voltage is applied between the electrode layer of the support substrate and the electrode layer of the movable thin film to cause the movable thin film to be deflected toward the support substrate by an electrostatic force acting between the electrode layers. A returning electrode is disposed on an side of the movable thin film opposite to the side which is opposed to the support substrate to apply an electrostatic force of attracting the movable thin film when a driving voltage is applied.
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