Patent ID: 8000031

Claim:
An imaging optical lens assembly comprising, 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 having a convex object-side surface and a concave image-side surface; a third lens element with positive refractive power having a concave object-side surface and a convex image-side surface; a fourth lens element with negative refractive power having a concave image-side surface, the object-side and image-side surfaces thereof being aspheric; and a fifth lens element having a concave image-side surface, the object-side and image-side surfaces thereof being aspheric; wherein the imaging optical lens assembly further comprises an aperture stop disposed between an imaged object and the second lens element, and an electronic sensor at an image plane for image formation; wherein a radius of curvature on the object-side surface of the first lens element is R1, a focal length of the imaging optical lens assembly is f, a distance on the optical axis between the aperture stop and the electronic sensor is SL, a distance on the optical axis between the object-side surface of the first lens element and the electronic sensor is TTL, and they satisfy the relation: 0.25 <R 1 /f< 0.50; 0.75 <SL/TTL< 1.10.