Lens barrel and a zoom lens barrel

摘要

A lens barrel includes first and second lens groups guided in an optical axis direction without rotating about the optical axis, first and second support frames which support the first and second lens groups and include first and second cam followers, respectively; and a cam ring which is rotatable about the optical axis and includes a cam groove. The cam groove is formed as a continuous groove and includes first and second groove portions via which the first and second cam followers are guided to move the first and second lens groups, respectively. One of the first cam follower and the second cam follower enters one of the first groove portion and the second groove portion after passing through the other of the first groove portion and the second groove portion in a preparation stage of the lens barrel.