A mirror drive portion which causes a mirror portion to swing around a predetermined swing axis; a single optical sensor including a single light emission portion and a single light reception portion which receives light emitted from the light emission portion; a light blocking portion which is arranged in the mirror portion to swing together with the swing of the mirror portion and periodically blocks the light emitted from the light emission portion along with the swing; and a mirror control portion which controls the swing of the mirror portion based on an alternating voltage and a detection signal of the optical sensor, wherein the mirror control portion acquires a state of the swing of the mirror portion based on a light reception state of the light reception portion and a zero-cross timing of the alternating voltage, and controls the swing of the mirror portion.