Patent ID: 7796346

Claim:
A zoom lens system, in order from an object side to an image side along an optical axis thereof, comprising: 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; wherein, during zooming from a wide-angle end to a telephoto end, the first lens groups moves toward the object side and the second lens groups moves toward the image side to increase a spacing between the first and second lens groups and to decrease a spacing between the second and third lens groups; and wherein the zoom lens system satisfies the following condition: 0.60 ≤ MG ⁢ ⁢ 1 · fw fT · Y ≤ 1.00 where MG 1 represents movement range of the first lens group when zooming from the wide-angle end to the telephoto end, fw represents focal length of the zoom lens system at the wide-angle end, fT represents focal length of the zoom lens system at the telephoto end, and Y represents a maximum diagonal length of an image plane.