Shutter and optical apparatus having the same

A shutter for an optical apparatus, the shutter having multiple sectors and an operation member, wherein:

• each of the multiple sectors has a cam opening for engagement and is pivotally provided to open and close a shutter opening;
• the operation member moves each of said multiple sectors in engagement with the cam opening;
• the cam opening of at least one sector that is one of the multiple sectors is formed to change a moving direction of said at least one sector, when the operation member moves said at least one sector to a position to close the shutter opening;
• said multiple sectors move to form a fully open state, a fully closed state, a small aperture state in this order, while the operation member is moving in one direction, the sectors including shutter blades and a small aperture blade;
• the shutter blades are respectively positioned on identical sides with respect to the position of the shutter opening in the fully open state and the small aperture state;
• the small aperture blade moves from the fully open state to the fully closed state to the small aperture state in a single direction;
• and
• the shutter blade is reciprocated in the fully closed state that serves as a turning point.