Patent ID: 8724235

Claim:
A photographing lens system comprising, in order from an object side to an image side: a first lens element with positive refractive power comprising a convex object-side surface and a convex image-side surface, and the object-side surface and the image-side surface being aspheric; a second lens element with negative refractive power comprising a concave object-side surface and a convex image-side surface, the second lens element being made of plastic and the object-side surface and the image-side surface being aspheric; and a third lens element with negative refractive power comprising an object-side surface and a concave image-side surface, the third lens element being made of plastic, the object-side surface and the image-side surface being aspheric, wherein the image-side surface is concave near an optical axis and convex away from the optical axis; the photographing lens system satisfying the following condition: −0.15<( R 1 +R 2 )/( R 1 −R 2 )<1.00; and 0 .70 mm<Σ CT< 1.56 mm; wherein R 1 is the curvature radius of the object-side surface of the first lens element, R 2 is the curvature radius of the image-side surface of the first lens element and ΣCT is the total central thickness of the lens elements with refractive powers; and wherein the total number of the lens elements with refractive powers is three.