Patent ID: 7872808

Claim:
A zoom lens system, comprising, in order from an object side to an image side: a first lens unit having positive optical power; a second lens unit having negative optical power; and a rear unit including at least one lens unit, wherein at least two lens units move during zooming so that intervals between the lens units adjacent to each other change; wherein the second lens unit consists of a negative lens component formed of at least one material and a positive lens element, which are arranged in the stated order from the object side to the image side; and wherein the following conditions are satisfied: 2.45< N 2 n −(9.3×10 −5 ×ν2 n 2 −1.70×10 −2 ×ν2 n )<3.00; 5<ν2 n< 80; and 1.98<( N 2 n+N 2 p )/2<2.25, where N 2 n represents a refractive index of the at least one material forming the negative lens component with respect to d-line, ν 2 n represents an Abbe number of the at least one material forming the negative lens component, and N 2 p represents a refractive index of a material forming the positive lens element with respect to d-line.