| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens system that is extremely thin when stored, has a wide field angle at the wide angle end and a zooming ratio of approximately three times, and to provide an imaging apparatus and a camera. SOLUTION: The zoom lens system includes a first lens group of negative power, a second lens group of positive power, and a third lens group of positive power. The first lens group has a first lens element of negative power which has a concave face on the image side and a second lens element of positive power which has a convex face on the object side. The second lens group comprises a cemented lens element composed of fourth and fifth lens elements of powers of different signs, and a sixth lens element which is single. For zooming, the first to third lens groups move along an optical axis. The zoom lens system satisfies the following conditions: 5.0<αi<SB>w</SB><20.0 and (n<SB>11</SB>-1)×(n<SB>12</SB>-1)≥0.84 (wherein 3.2<f<SB>T</SB>/f<SB>w</SB>,ω<SB>w</SB>>35,αi<SB>w</SB>represents an angle at which the principal light ray of the maximum height image at the wide angle end enters the imaging element, n<SB>11</SB>and n<SB>12</SB>each represent the refractive index of the second lens element,ω<SB>w</SB>represents a half field angle at the wide angle end, f<SB>T</SB>represents the focal distance of the entire system at the telephoto end, and f<SB>w</SB>represents the focal distance of the entire system at the wide angle end). The imaging apparatus and camera are also provided. COPYRIGHT: (C)2009,JPO&INPIT
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