| 摘要 |
PROBLEM TO BE SOLVED: To provide a high variable power zoom lens that has a magnification of three times or more while having a sufficient wide angle area and a compact configuration. SOLUTION: The zoom lens includes, in order from the object side, a first lens group having a negative refracting power, a second lens group having a positive refracting power, and a third lens group having a positive refracting power, changes distances between the lens groups to vary a magnification, and satisfies four conditional equations (1) to (4); (1) 0.80<IH/f<SB>w</SB><1.5, (2) 2.7<f<SB>t</SB>/f<SB>w</SB><12, (3) 0.05<¾d<SB>a</SB>/f<SB>1G</SB>¾<10, and (4) 0<d<SB>b</SB>/f<SB>2G</SB><3, where IH is photographing image height of the zoom lens, f<SB>w</SB>is the focal length at the wide angle end of the total system of the zoom lens, f<SB>t</SB>is the focal length at the telephoto end of the total system of the zoom lens, f<SB>1G</SB>is the focal length of the first lens group, f<SB>2G</SB>is the focal length of the second lengs group, and d<SB>a</SB>is the on-axis interval between the first lens group and the second lens group when the total system of the zoom lens has any focal length f<SB>ra</SB>satisfying the condition (a) of IH/0.92<f<SB>ra</SB><IH/0.8, wherein d<SB>b</SB>is the on-axis internal between the first lens group and the second lens group when the total system of the zoom lens group has any focal length f<SB>rb</SB>satisfying the condition (b) of 2.7<f<SB>rb</SB>/f<SB>ra</SB><5. COPYRIGHT: (C)2007,JPO&INPIT
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