Patent ID: 8264781

Claim:
A zoom lens comprising: a first lens group having a positive refracting power, a second lens group having a negative refracting power, a third lens group having a positive refracting power, and a fourth lens group having a positive refracting power, which are disposed in order from an object side to an image side; and an aperture stop disposed at an object side of the third lens group, the second lens group including a negative lens, a positive lens, and a negative lens, which are disposed in order from the object side, wherein when changing the magnification of the zoom lens from a wide angle end to a telephoto end, an interval between the first and second lens groups increases, an interval between the second and third lens groups decreases, and an interval between the third and fourth lens groups changes; and the following conditions (1) and (9) are satisfied: 0.50< fl/ft< 0.80; (1) 0.78≦ Y′/fw, (9) where fl is a focal length of the first lens group, ft is a focal length of the zoom lens at the telephoto end, Y′ is a maximum image height, and fw is a focal length of the zoom lens at the wide angle end, wherein as the magnification of the zoom lens changes from the wide angle end to the telephoto end, the first and third lens groups are moved toward the object side, the second lens group is moved toward the image side, and the fourth lens group is moved on a trajectory in a curve convex toward the object side.