Abstract: A high zoom ratio wide-angle zoom lens system includes a first lens group comprising a first lens of biconcave, a second lens of positive meniscus, a third lens of biconvex, and a fourth lens of biconvex wherein the first lens and the second lens are lenses not cemented together by adhesive; a second lens group comprising a fifth lens of positive meniscus, a sixth lens of biconcave, a seventh lens of biconvex, and an eighth lens of plano-concave; a third lens group comprising a ninth lens of biconvex; and a fourth lens group comprising a tenth lens of biconvex, an eleventh lens of plano-concave, a twelfth lens of biconvex, and a thirteenth lens of biconcave. The zoom lens system has a wide angle of view of at least 70-degree, high zoom ratio, and other advantages.

Abstract: A zoom lens system is disclosed that includes a front first lens group including a first lens of divergent meniscus and a second lens of plano-convex; an intermediate second lens group including a third lens of plano-concave, a fourth lens of plano-concave, and a fifth lens of plano-convex; and a rear third lens group including a sixth lens of double-convex, a seventh lens of double-convex, an eighth lens of plano-concave, and a ninth lens of plano-concave. The sixth and ninth lenses are non-spherical lenses formed of a plastic material, and the zoom lens system satisfies the following conditions (a) 0.16<fw/f1<0.21 (b) ?0.78<fw/f2<?0.64 (c) 0.70<fw/f3<0.75 (d) 0.47<log Z3/log Z<0.76.