Patent attributes
An imaging lens comprises, in order from an object side:a first lens having a positive refractive power;a second lens having a negative refractive power whose concave surface faces to the object; anda third lens having a positive refractive power and having a meniscus form that has a convex surface, facing to the object, in a portion at and around an optical axis of the imaging lens;wherein the first, second and third lenses have at least one aspheric surface, andwherein the imaging lens satisfies conditional expressions given below:0.7<f1/f<1.3 (1)0.3<D2/f<0.5 (2)1.0<|f2/f|<3.0 (3)1.2<f3/f<4.0 (4)wheref: a focal length of an overall system,f1: a focal length of the first lens,f2: a focal length of the second lens,f3: a focal length of the third lens, andD2: a spacing, on the optical axis, between the first lens and the second lens.
