Patent ID: 7196850

Claim:
A zoom lens comprising, in order from an object side to an image side: a first lens unit having a negative refractive power; a second lens unit having a positive refractive power; and a third lens unit having a negative refractive power, wherein the second and third lens units move in zooming; and wherein the first, second, and third lens units each comprise one or more lenses having refractive powers of the same sign, and wherein the first, second, and third lens units satisfy the following conditions: 1.2<|φ1/φ T |<2 0.9<φ2/φ T< 2.2 0.75<φ3/φ1<1.2 wherein φ 1 , φ 2 , and φ 3 are the refractive powers of the first, second, and third lens units, respectively, and φT is the refractive power of the zoom lens at a telephoto end.