| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a zoom lens which is compact and has high optical performance all over the zoom range. Ž<P>SOLUTION: The zoom lens has, in order from the object side, a first lens group with a negative focal length, a second lens group with a positive focal length, a third lens group with a negative focal length, and a fourth lens group with a positive focal length. During zooming from a wide-angle end to a telephoto end, the first lens group moves along a locus having a convex shape toward an image side while decreasing an air space between the first and second lens groups, and the second and third lens groups move toward the object side while increasing an air space therebetween. The surface nearest to the object side of the second lens group is arranged to turn a convex surface to the object side and has an aspherical surface, and the second lens group includes one cemented lens comprising a negative meniscus lens turning its convex surface to the object side and a positive lens. The cemented lens satisfies a conditional expression (1) 0.3<R<SB>CL</SB>/f2<1.0. Provided that R<SB>CL</SB>is a radius of curvature of a cemented surface of the cemented lens constituting the second lens group, and f2 is a focal length of the second lens group. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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