Patent ID: 8520324

Claim:
An imaging lens system including, in order from an object side to an image side: a first lens element with positive refractive power having a convex object-side surface; a second lens element with negative refractive power; a third lens element; a fourth lens element with positive refractive power having a convex image-side surface; a fifth lens element with negative refractive power having a concave image-side surface, at least one surface thereof being provided with at least one inflection point; and an aperture stop disposed between an imaged object and the third lens element; wherein a radius of curvature of the object-side surface of the first lens element is R1, a focal length of the imaging lens system is f, an Abbe number of the first lens element is V1, an Abbe number of the second lens element is V2, and R1, f, V1, and V2 satisfy the relations: 0.2<R1/f<0.4; and V1−V2>20.