ACTUATOR

摘要

A reflection part (121) is formed on one surface of a planar movable part (120) of an actuator (1), and one or a plurality of ribs (123) for maintaining flatness of the movable part are formed on another surface opposite to the one surface of the movable part. A first rib included in the one or the plurality of ribs extends in a lateral direction on the other surface. A side surface of the first rib on a side of the torsion bar is concave in a portion that is away from the rotation axis, in a plane view on the other surface, and a degree of a concave of the side surface in the portion that is away from the rotation axis is greater than a degree of a concave of the side surface in the vicinity of the rotation axis.