Patent ID: 8721533

Claim:
An image pickup apparatus comprising: a movable lens unit having a movable lens frame holding a movable lens; a fixed lens frame in which a plurality of objective optical systems are disposed, and in which the movable lens unit is held so as to be able to advance and retract in a shooting optical axis direction; a diaphragm unit which has a diaphragm blade formed of a magnetic material and movable in a first direction and a second direction opposite to the first direction, and adjusts an amount of shooting light by moving the diaphragm blade; a first urging member provided at the movable lens unit and including a first magnet which urges the diaphragm blade in the first direction by a first magnetic force as a first urging force according to the advancement and retraction of the movable lens unit; and a second urging member which urges the diaphragm blade in the second direction by a second urging force smaller than the first urging force, wherein, according to the advancement and retraction of the movable lens unit, when the first urging member moves close to the diaphragm blade, the diaphragm blade moves in the first direction by receiving the first urging force against the second urging force, and when the first urging member moves away from the diaphragm blade, the diaphragm blade moves in the second direction by receiving the second urging force.