| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens which has high resolution, whose distortion aberration is small and which is compact when it is collapsed and housed by effectively arranging an aspherical lens. SOLUTION: The zoom lens is constituted of a first lens group, a second lens group and a third lens group in order from an enlargement side. The first lens group has negative refractive power and is constituted by arranging a first lens that is a lens having negative refractive power (hereinafter referred to as a negative lens), and a second lens that is a meniscus lens having positive refractive power (hereinafter referred to as a positive lens). The second lens group has positive refractive power and is constituted by arranging a third lens that is a positive lens, a fourth lens which has one or more aspherical surfaces and whose power is small, a fifth lens that is a positive lens and a sixth lens that is a negative lens used in a cemented state with the fifth lens. The third lens group is constituted by arranging a seventh lens that is a positive lens. By positionally moving the first lens group, the second lens group and the third lens group, magnification is varied. COPYRIGHT: (C)2008,JPO&INPIT
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