1. A scanner comprising:an optical fiber that guides light from a light source;
a drive unit comprising at least one actuator that, when a voltage is applied thereto, displaces an exit end of the optical-fiber in a direction intersecting an optical axis;
a support portion that is provided on a basal end side from the drive unit and that is spaced from the drive unit to support the optical fiber; and
a correction portion that is configured to shift a first combined center of gravity of both of the drive unit and the correction portion, so that the combined center of gravity substantially coincides with a second combined center of gravity of both of the optical fiber and the support portion in a radial cross section of the optical fiber,
wherein the drive unit comprises a polygonal tubular oscillation propagation member that has a through-hole in an axial direction thereof and that is composed of a material configured to propagate oscillation, wherein the optical fiber passes through the through-hole of the oscillation propagation member, and the actuator is fixed to the outer surface of the oscillation propagation member, and
wherein the drive unit comprises at least two of the actuators, which produces oscillations in a radial direction of the optical fiber, and the actuators adjacent to each other in a circumferential direction are arranged so as to be spaced apart by substantially 90° in a circumferential direction of the optical fiber.