Lens barrel and optical apparatus

摘要

A lens barrel includes an image-pickup optical system that includes a main optical system and an extender optical system, an extender barrel configured to hold the extender optical system, a housing configured to house the extender barrel, a rotator configured to hold the extender barrel to rotatably support the extender barrel in the housing, to insert the extender optical system into the main optical system, and to retreats the extender optical system from the main optical system, and a retreat restraint. When the retreat restraint is in the first state, the extender optical system is retreated to a position which is not associated with formation of the optical image, but the extender optical system is undetachable from the rotator, and when the retreat restraint is in the second state, the extender optical system is detachable from the rotator.

主权项

1. A lens barrel comprising:
an image-pickup optical system configured to form an optical image of an object, the image-pickup optical system including a main optical system and an extender optical system configured to change a focal length of the image-pickup optical system; an extender barrel configured to hold the extender optical system; a housing configured to house the extender barrel; a rotator configured to:
hold the extender barrel to rotatably support the extender barrel in the housing;insert the extender optical system into the main optical system; andretreat the extender optical system from the main optical system; and a retreat restraint having a first state used to restrain a retreating amount of the extender barrel by the rotator and a second state used to make the retreating amount of the extender barrel larger than that in the first state, wherein, when the retreat restraint is in the first state, the extender optical system is retreated to a position that is not associated with formation of the optical image, but the extender barrel is undetachable from the rotator, and wherein, when the retreat restraint is in the second state, the extender barrel is detachable from the rotator.