Patent ID: 8873155
Filing Date: 2014-10-28
Classification: G02B

Abstract:
1. A zoom lens comprising, in order from an object side to an image side: a first lens unit having positive refractive power; a second lens unit having negative refractive power; a third lens unit having positive refractive power; and a rear lens group including one or more lens units, wherein, at a telephoto end compared with a wide-angle end, a distance between the first lens unit and the second lens unit becomes larger, a distance between the second lens unit and the third lens unit becomes smaller, and a distance between the third lens unit and the rear lens group changes, wherein the rear lens group has positive refractive power in an entire zoom range from the wide-angel end to the telephoto end, and an aperture stop is arranged between a lens surface of the second lens unit closest to the image side and a lens surface of the third lens unit closest to the image side, wherein the third lens unit includes, in order from the object side to the image side, a first positive lens including an aspheric surface, a second positive lens including an aspheric surface, and a negative lens, and wherein, when a refractive index of a material of the first positive lens at d-line is nd31, and an Abbe number and relative partial dispersion of a material of the second positive lens are νd32 and θgF32, respectively, conditions below are satisfied: