Patent ID: 10095011

Abstract:
A zoom lens system includes a positive first lens group, a negative second lens group, a positive third lens group and a positive fourth lens group, in that order from the object side, wherein distances between adjacent lens groups thereof change during zooming. The third lens group includes a positive first sub-lens group, a positive second sub-lens group and a negative third sub-lens group. The third sub-lens group consists of a single negative lens element. The following conditions (1) and (2) are satisfied: 6.0<f1Gp/fw<9.0  (1), and1.3<f3Gp/f4Gp<2.0  (2), wherein fw designates the focal length of the entire zoom lens system at the short focal length extremity, f1Gp, f3Gp and f4Gp designate the focal lengths of the first, third and fourth lens groups, respectively.