A pair of substrate portions each being tabular-shaped has side portions located closer to a mirror portion and connected, at both ends thereof in the oscillation axis direction, by a pair of supporting beam portions, and also has outer side portions fixed to a fixing member. An excitation device is formed on at least one substrate portion. The pair of substrate portions is disposed symmetrically in the direction perpendicular to the oscillation axis. A pair of torsion beam portions extends outward from two opposite sides of the mirror portion on the oscillation axis, and each is connected to the center of each supporting beam portion in a longitudinal direction. An edge of the piezoelectric element on an outer side thereof in the direction perpendicular to the oscillation axis is spaced from an outer side portion of the at least one substrate portion in a direction closer to the mirror portion.