Zoom lens system

A zoom lens system comprising, in order from the object side:

• a positive first lens group and a negative second lens group, said first lens group and second lens groups adjusting a magnification factor of the zoom lens system by varying a distance therebetween, said first lens group comprises, in order from the object side, a first positive meniscus lens element having a convex surface that is directed toward an object, a first negative lens element having a concave surface that is directed toward the object, a second positive lens element having a convex surface that is directed toward an image plane and separated from said first negative lens element by an air gap, and a positive cemented lens which includes a third positive lens element and a second negative lens element, said third positive lens element being cemented to a concave surface of said second negative lens element that is directed toward the object;
• said first and second lens groups satisfying the following conditions:
• 1.59<fw/f1<2.0, and
• 1.79<fw/f2<2.5;
• where fw represents a focal length of the overall zoom lens system at a wide-angle end, f1 represents a focal length of said first lens group, and f2 represents a focal length of said second lens group.

A zoom lens system comprising, in order from the object side:

• a positive first lens group and a negative second lens group, said first lens group and second lens groups adjusting a magnification factor of the zoom lens system by varying a distance therebetween, said first and second lens groups satisfying the following conditions:
• 1.59<fw/f1<2.0, and
• 1.79<fw/f2<2.5;
• where fw represents a focal length of the overall zoom lens system at a wide-angle end, f1 represents a focal length of said first lens group, and f2 represents a focal length of said second lens group;
• said second lens group comprises, in order from the object side, a first positive meniscus lens element having a convex surface directed toward an image plane and first and second negative meniscus lens elements, each having a concave surface directed toward an object, said second lens group satisfying the following conditions:
• -0.7<r22/fw<-0.25
• -0.7<r23/fw<-0.19, and
• -0.7<r25/fw<-0.19;
• where r2i represents a radius of curvature of an ith lens surface in the second lens group as counted from an object side, i being an integer;
• said first positive meniscus lens element having a concave surface directed toward the object, which is an aspheric surface that satisfies the following condition:
• 0<.DELTA.V2<0.2;
• where .DELTA.V2 represents an amount of variation in a coefficient of distortion due to the aspheric surface in the second lens group when an overall focal length of the zoom lens system at the wide angle end equals unity.