| 摘要 |
PROBLEM TO BE SOLVED: To obtain a compact camera zoom lens system whose entire length and size are both small while maintaining a high zoom ratio in a zoom lens system constituted of two positive and negative groups. SOLUTION: Either a first lens group or a second lens group has two or more subgroups, and either subgroup is set as a changeover group which is movable to the moving end of either an object side or an image surface side with reference to the other subgroup, and it is moved to the object side while changing the distance of two groups in the state of holding the changeover group at the moving end of the object side a short focal distance side zooming area reaching from fw to fm, and the changeover group is moved to the moving end of the image surface side, and also two groups are respectively moved to the image surface side in the zooming area fm, and it is moved to the object side while changing the distance of two groups in the state of holding the changeover group at the moving end of the image surface side in a long focal distance side zooming area reaching from fm to ft. Then, fw means the distance at a short focal distance end, and ft means the focal distance at a long focal distance end and fm means an intermediate changeover focal distance.
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