| 摘要 |
PROBLEM TO BE SOLVED: To obtain the angle of view at a wide-angle end being >=60 deg.C even when a zoom variable power ratio is about 2 to excellently compensate aberration all over the zoom area and to shorten the entire length of a lens in a collapsed state by providing the lens with 1st and 2nd lens groups and making it satisfy a specified condition. SOLUTION: The 1st lens group is constituted of a negative lens group G11 and a positive lens group G12 in order from an object side. The lens group G11 is constituted of a biconcave lens L1 which has a larger curvature on an image side and a negative meniscus lens L2 whose convex surface faces to the object side, and the lens group G12 is constituted of a positive lens L3. The 2nd lens group is constituted of a positive lens L4 and a negative lens L5 in order from the object, and the zoom lens satisfies conditional expressions 0.2<|fG11/D|<1.8,νL4<50 and VL5<70. In the conditional expressions, fG11 is the focal distance of the lens group G11, D is the length of the diagonal of a photographic image plane,νL4 is the Abbe number of the positive lens L4 andνL5 is the Abbe number of the negative lens L5. Thus, the excellent performance is obtained in the entire system even in the case of shortening the entire length of the lens.
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