Patent ID: 8169711

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, and a rear group including at least one lens unit, in order from an object side to an image side, wherein each of the lens units is configured to move so that a total lens length at a telephoto end is longer than that at a wide-angle end to perform a zoom operation, and wherein the conditional expressions 20.0 <f 1 /fw< 50.0 7.5 <M 1 /fw< 40.0 0.2 <M 1 /ft< 0.8 are satisfied, where M 1 is a movement amount of the first lens unit when zooming from the wide-angle end to the telephoto end with respect to an imaging surface, f1 is a focal length of the first lens unit, and fw and ft are focal lengths of a whole system at the wide-angle end and the telephoto end.