| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens which can reduce occurrence of chromatic aberration at the telephoto end, has a wide angle of view and a high zoom ratio, and achieves excellent optical performance over the entire zoom range.SOLUTION: The zoom lens includes, in order from the object side to the image side: a first lens group having a positive refractive power; a second lens group having a negative refractive power; an aperture stop; a third lens group having a positive refractive power; and a rear group having one or more lens groups, and performs zooming operation by changing the distances between the lens groups. In the zoom lens, the positions of the first lens group and the aperture stop move nearer to the object side at the telephoto end than at the wide-angle end. The third lens group includes one or more positive lenses. A partial dispersion ratio &thetas;gF3P of the material of one positive lens in the third lens group, the Abbe number &ngr;d3P thereof, the focal length fT of the entire system at the telephoto end, and the focal length f3 of the third lens group are appropriately set, respectively. |
