Patent ID: 7566179

Claim:
A lens barrel comprising: lenses provided in a lens chamber within the lens barrel; a lens barrier that is opened and closed in front of the lenses; and a barrier block that is provided near an inlet of the lens chamber so as to be movable along an optical axis, is capable of holding the lens barrier in an open state and a closed state, comprises a barrier retraction space where the lens barrier in the opened state is received, and changes a volume of a rear portion of the lens chamber according to a movement of the barrier block along the optical axis, wherein: the barrier block has a drain hole which communicates the barrier retraction space with an outside of the lens barrel, and an air passage formed near the drain hole which communicates the barrier retraction space with the rear portion of the lens chamber, such that an air flow directed from the rear portion of the lens chamber toward the barrier retraction space is generated in the air passage when the barrier block moves backward.