Patent ID: 7428107

Claim:
A zoom lens comprising: a first lens unit having a positive refractive power; a second lens unit having a negative refractive power; a third lens unit having a positive refractive power; a fourth lens unit having a negative refractive power; and a fifth lens unit having a positive refractive power, the first to fifth lens units being arranged from an object side to an image side in that order, wherein the zoom lens performs zooming by moving the first to fifth lens units from a wide-angle end to a telephoto end such that a distance between the first lens unit and the second lens unit increases, a distance between the second lens unit and the third lens unit decreases, a distance between the third lens unit and the fourth lens unit increases, and a distance between the fourth lens unit and the fifth lens unit decreases, wherein the fourth lens unit consists of a negative lens, the fourth lens unit being moved in such a manner so as to have a component in a direction orthogonal to an optical axis so as to shift an image formed with an entire system in the direction orthogonal to the optical axis, and wherein the following condition is satisfied: 0.50<| ft/f 4|<1.50, where ft is a focal length of the entire system, and f4 is a focal length of the fourth lens unit, both at the telephoto end.