| 摘要 |
A lens barrel includes a cam ring (5) that determines the position of a first lens frame (11) in the optical axis direction; a first correcting tube (1) that is made of a material having a coefficient of linear expansion different from that of the cam ring (5) and determines the position of the cam ring (5) in the optical axis direction; and a second correcting tube (2) that is made of a material having a coefficient of linear expansion different from that of a movable frame (6) and determines the position of a second lens frame (21) in the optical axis direction, wherein integrally with a change in the dimension of the first correcting tube (1) in the optical axis direction due to a temperature change, the cam ring (5) moves in the optical direction, and at the same time the first and second lenses (10, 20) move in the optical axis direction; and integrally with a change in the dimension of the second correcting tube (2) in the optical axis direction due to the temperature change, the second lens (20) moves in the optical axis direction, and the distance between the first lens (10) and the second lens (20) changes.
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