Patent ID: 6989947

Claim:
An imaging lens comprising a first lens L 1 , an aperture diaphragm S 1 , a second lens L 2 , and a third lens L 3 , and constituted such that said first lens L 1 , said aperture diaphragm S 1 , said second lens L 2 , and said third lens L 3 are arranged in succession from the object side to the image side, wherein said first lens L 1 is a resin lens having a positive refractive power and a meniscus shape in which the convex surface faces the object side, said second lens L 2 is a resin lens having a positive refractive power and a meniscus shape in which the convex surface faces the image side, and said third lens L 3 is a resin lens having a negative refractive power, both surfaces of said first lens L 1 being aspherical, both surfaces of said second lens L 2 being aspherical, and at least one surface of said third lens L 3 being aspherical, and said imaging lens satisfying the following conditions, 0.40 <r 1 /r 2 <0.65 (1) 0.08 <D 2 /f <0.1 (2) 0.2 <D 3 /f <0.3 (3) 1.0 <d/f <1.5 (4) 0.4 <b f /f <0.6 (5) where f is the focal length of the entire lens system, r 1 is the radius of curvature of the object-side surface of the first lens L 1 in the vicinity of the optical axis, r 2 is the radius of curvature of the image-side surface of the first lens L 1 in the vicinity of the optical axis, D 2 is the interval between the first lens L 1 and second lens L 2 , D 3 is the thickness at the center of the second lens L 2 , d is the distance from the object-side surface of the first lens L 1 to the imaging surface, and b f is the distance from the image-side surface of the third lens to the imaging surface.