Patent ID: 8891173

Claim:
A zoom lens comprising, in order from an object side to an image side: a first lens unit having a positive refractive power; a second lens unit having a negative refractive power; an aperture stop; 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, wherein during zooming from a wide-angle end to a telephoto end, the first lens unit is configured to remain stationary, the second lens unit, the third lens unit, and the fourth lens unit are configured to move separately from one another, and the aperture stop is configured to move along a locus convex towards the object side, wherein, when f3 is a focal length of the third lens unit and DS3 is an interval between the aperture stop and the third lens unit at a zooming position at which the aperture stop is located closest to the object side, the following condition is satisfied: 0.5 <DS 3 /f 3<2.0.