| 摘要 |
A zoom lens barrel includes front and rear lens group support frames, a first spring member provided to bias the front lens group support frame and a diaphragm in directions away from each other, and a second spring member provided to bias the diaphragm and the rear lens group support frame in directions away from each other. Spring loads of the first and second spring members are determined such that, when the front and rear lens group support frames approach each other during zooming, one and the other of the first and second spring members are compressed and not compressed, and the other of the first and second spring members is compressed after the one of the first and second spring members is fully compressed. |
