Patent ID: 7864445
Filing Date: 2011-01-04
Classification: G02B

Abstract:
1. 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 which has a negative refractive power and includes a negative lens; and a subsequent lens group including at least one lens unit, wherein at least the second lens unit is moved on an optical axis so as to increase an interval between the first lens unit and the second lens unit during zooming from a wide angle end to a telephoto end, wherein the first lens unit comprises: a front lens subunit which is not moved during focusing and has a positive refractive power; and a rear lens subunit which is moved during the focusing and has a positive refractive power, wherein the rear lens subunit includes a positive lens, where νd denotes an Abbe number of the material and θgF denotes a partial dispersion ratio of the material.