Patent ID: 8089700

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, the second lens unit including a positive lens; and a third lens unit having a positive refractive power, the third lens unit including a positive lens, wherein intervals between adjacent ones of the first lens unit, the second lens unit, and the third lens unit are variable during zooming, wherein a refractive power of a material of the positive lens included in the second lens unit (Nd 2 P), an Abbe number of the material of the positive lens included in the second lens unit (νd 2 P), a focal length of the third lens unit (f 3 ) and a radius of curvature of a surface on the object side of the positive lens included in the third lens unit (R 31 ) satisfy the following conditions: Nd 2 P+ 0.01 ×νd 2 P> 2.3, 1.65<Nd2P<2.7, νd2P>45, and 0.7 <R 31 /f 3<1.0, wherein the second lens unit further includes a plurality of negative lenses, and wherein the positive lens included in the second lens unit is located adjacent to and on an object side of a negative lens having the shortest focal length of the focal lengths of the plurality of negative lenses.