Patent ID: 8179609

Claim:
A zoom lens comprising, in order from an object side to an image side: a first lens unit having a positive refractive power which does not move for zooming; a second lens unit having a negative refractive power which moves during zooming; a third lens unit having a negative refractive power which moves during zooming; a fourth lens unit having a positive refractive power which moves during zooming; and a fifth lens unit having a positive refractive power which does not move for zooming, wherein the second lens unit moves to the image side during zooming from a wide angle end to a telephoto end, while the third lens unit moves so as to take a locus convex toward the object side, and wherein, when fw denotes a focal length of the entire system at the wide angle end, Z denotes a zoom ratio, and fz denotes a focal length of the entire system at a zoom position where the third lens unit is in the position closest to the object side, the following conditional expression is satisfied: fw×Z 0.07 <fz<fw×Z 0.5 .