Patent ID: 7742238

Claim:
An imaging lens comprising, in order from an object side: a first lens having a positive refractive power and having a meniscus shape with a convex surface directed to the object side thereof; a second lens having a concave object-side surface; and a third lens that has a negative refractive power in a vicinity of an optical axis, wherein each of the second and third lenses has at least one aspheric surface, and the following conditional expressions are satisfied: 0.8< f 1/ f< 1.2 (1) 11<| f 2/ f| (2) 0.04< SA/Y< 0.09 (3) TL/ 2 Y< 0.9 (4) where f denotes a focal length of the entire system, f1 denotes a focal length of the first lens, f2 denotes a focal length of the second lens, SA denotes the amount of sag of the object-side surface of the second lens in a position where a principal ray passes the maximum image height, Y denotes the maximum image height, and TL denotes a distance from an object-side surface of the first lens to an image formation position.