| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens capable of attaining resolution coping with an image sensor that has a half field view of 38°or more at wide angle end, a variable power ratio of five times or more, and about five to ten million pixels. SOLUTION: The zoom lens includes, in order from the object side along an optical axis: a first lens group I having positive refractive power and fixed when power is varied; a second lens group II having negative refractive power; a third lens group III having positive refractive power; a fourth lens group IV having positive refractive power; a fifth lens group V having negative refractive power; and a sixth lens group VI having positive refractive power. When varying power from the wide angle end to the telephoto end, at least the second, fourth, and fifth lens groups are moved to vary power. The first lens group is the zoom lens having a reflecting optical element for bending an optical path. In this zoom lens, at least an additional lens group VII having negative refractive power is additionally inserted in the groups of the zoom lens, thereby varying power more on the long focal length side from the telephoto end. COPYRIGHT: (C)2009,JPO&INPIT
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