Patent ID: 8351128

Claim:
A zoom lens consisting of: 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 positive refractive power, wherein the first lens unit, the second lens unit, and the third lens unit are arranged in order from an object side to an image side, wherein distances between the first, second, and third lens units change during zooming, wherein the first lens unit consists of two lenses, and wherein the following conditions are satisfied: −0.587 ≦fl/ft<− 0.20 −0.39<( R 2 r−R 1 f )/( R 2 r+R 1 f )<0.36 where R1f and R2r represent radii of curvature of a lens surface closest to the object side in the first lens unit and a lens surface closest to the image side in the first lens unit, fl represents a focal length of the first lens unit, and ft represents a focal length of the entire zoom lens at a telephoto end.