Patent ID: 7486882

Claim:
A lens unit, comprising: a lens barrel; an imaging optical system in the lens barrel; a movable part having a movable lens, the movable part being moveable in an optical axis direction with respect to the lens barrel; a linear actuator for driving the movable part in the optical axis direction; and a pair of biasing plate springs, the springs having a holding section for holding the movable part, spring sections that can be resiliently deformed for biasing the movable part in the optical axis direction, and attached sections attached to the lens barrel, wherein a thickness direction of the biasing plate springs coincides with the optical axis direction, wherein the holding section of the biasing plate springs forms a circular arc, wherein at least a portion of the spring sections of the biasing plate springs has a shape extending in a direction substantially along the holding section on an outer peripheral side of the holding section, and wherein a spring force of one of the pair of biasing plate springs is larger than a spring force of the other of the pair of biasing plate springs for holding the moveable part at one end of the lens barrel when the linear actuator is not driving the moveable part.