Mirror rotating apparatus

摘要

A mirror rotating apparatus includes a stationary portion (3) and a rotating portion (2). The stationary portion (3) includes a detection sensor (36) configured to detect rotation of the rotating portion (2). The rotating portion (2) includes a mirror portion (24) whose outside surface includes a plurality of mirror surfaces (262) that face radially outward. The mirror portion (24) includes a rotation detection surface (261) opposite to the detection sensor (36), and a balance correction portion (27) defined by a groove (27) or a projection extending in a circumferential direction in the rotation detection surface (261). The balance correction portion (27) locates a center of gravity of the mirror portion (24) closer to the rotation axis (J1). The rotation of the rotating portion (2) causes the balance correction portion (27) to pass through a region to which light is emitted from the detection sensor (36).