Patent ID: 7580624

Claim:
A position detecting device detecting a position of a frame that holds a lens in a lens tube, the position detecting device comprising: an optical sensor unit arranged on any one of the lens tube and the frame; and a detection target unit arranged on either one of the lens tube and the frame on which the optical sensor unit is not arranged, the detection target unit to be detected by the optical sensor unit, wherein the detection target unit includes a target member detected by the optical sensor unit; and a shielding unit configured to cover the optical sensor unit and the target member at a time of detection, wherein the target member includes a protrusion along the optical axis, and the shielding unit is formed along the optical axis near the target member so as to cover an outer side of the optical sensor unit at least during the detection of the position, and includes a pair of walls arranged to face each other in a direction perpendicular to the optical axis, sandwiching the target member; and a bottom wall arranged on a side of a base of the target member, and configured to connect the pair of walls.