Zoom lens barrel for moving lenses in the optical axis direction without increasing the length of the zoom lens barrel

摘要

A zoom lens barrel attains zooming by moving at least some lenses in the optical axis direction, has a cylindrical lens frame which holds the lenses on its inner circumferential surface side, is formed with a lens cam slot having a spiral shape about the optical axis, is formed with a straight slot extending in a direction parallel to the optical axis, and is movable in the optical axis direction. A cylindrical cam barrel is rotatable about the optical axis and is movable in the optical axis direction. A cylindrical stationary barrel is formed with a cam barrel cam slot having a spiral shape about the optical axis, a lens cam pin, one end portion of which is fixed to the cam barrel, and the other end portion of which is fitted in the lens cam slot of the lens frame, a cam barrel cam pin, one end portion of which is fixed to the cam barrel, and the other end portion of which is fitted in the cam barrel cam slot of the stationary barrel, a lens frame rotation regulation member which is not rotatable about the optical axis direction, and is inserted in the straight slot of the lens frame, and a zoom operation ring which is attached to the stationary barrel to be rotatable about the optical axis, and rotates the cam barrel cam pin without regulating movement, in the optical axis direction, of the cam barrel cam pin.