Patent ID: 8670184

Claim:
A zoom lens system comprising a negative first lens group, a positive second lens group, and a positive third lens group, in that order from the object side, wherein upon zooming from the short focal length extremity to the long focal length extremity, the distance between said first lens group and said second lens group decreases and the distance between said second lens group and said third lens group changes, in the optical axis direction, wherein said second lens group includes a biconvex positive lens element provided with an aspherical surface on each side thereof, and a negative meniscus lens element provided with an aspherical surface on at least one surface thereof and having a concave surface on the image side, in that order from the object side, and wherein the following conditions (1) and (2) are satisfied: ν d> 80 (1), and Pg — F >0.53 (2), wherein νd designates the Abbe number with respect to the d-line of the biconvex positive lens element that is provided within said second lens group, and Pg_F designates the partial dispersion ratio of the biconvex positive lens element that is provided within said second lens group.