Patent ID: 7177095

Claim:
A zoom lens, comprising in order from the object side to the image side: a first lens group of negative refractive power; a second lens group of positive refractive power; and a third lens group, wherein the first lens group and the second lens group move at the time of zooming, and wherein the first lens group consists, in order from the object side to the image side, a first lens of negative refractive power, and a second lens of positive refractive power, wherein said first lens group moves to the image side so as to draw a convex locus at the time of zooming from the wide-angle end to the telephoto end, and said second lens group moves to the object side, and wherein, with the focal distance of the first lens group as f 1 , the focal distance of the second lens group as f 2 , the focal distance of the entire system at the wide-angle end as fw, and the focal distance of the entire system at the telephoto end as ft, the following conditions are satisfied: 1.5 ≦ft/fw; and 1.75< |f 1/ |f 2<2.5.