Patent ID: 7268955

Claim:
A zoom lens, which comprises a first lens group of positive power, a second lens group of negative power and a third lens group of positive power and in which upon zooming, the first lens group remains fixed and the second lens group and the third lens group are movable, wherein: the first lens group comprises a subgroup 1 A of negative power and a subgroup 1 B of positive power, the second lens group comprises a first negative lens, a cemented positive lens, a second negative lens and a third negative lens, and the following conditions (1) and (2) are satisfied: 10<| f 1A /f w |<50 (1) 0.7<| f 2 /f w |<1.1 (2) where f 1A is a focal length of the subgroup 1 A, f 2 is a focal length of the second lens group, and f w is a focal length of the whole zoom lens system at a wide-angle end.