| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens having a wide angle of view, a high zoom ratio and high optical performance in the entire zoom range. SOLUTION: The zoom lens comprises a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, and a fourth lens group having positive refractive power in order from an object side to an image side. In the zoom lens, the second lens group and the fourth lens group are moved in zooming. The second lens group comprises a 21st lens having negative refractive power, a 22nd lens having negative refractive power, a 23rd lens having negative refractive power, and a 24th lens having positive refractive power in order from the object side to the image side. The focal length fw of an overall system at a wide angle end, the focal length ft of an overall system at a telephoto end, the focal length f2 of the second lens group, a distance TL on an optical axis from a lens surface on the side closest to an object to an image surface when a distance from a lens surface on the side closest to an image to an image surface is calculated by aerial conversion, and a distance D2 on the optical axis from the lens surface on the side closest to the object of the second lens group to the lens surface on the side closest to the image of the second lens group are respectively and appropriately set. COPYRIGHT: (C)2011,JPO&INPIT
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