US Patent 7535660 Imaging lens

An imaging lens is used for forming an image of an object on an image-taking surface of a solid state image sensor element and includes, in order from an object side to an image surface side, a diaphragm, a first lens which is a meniscus lens having a positive power whose convex surface faces the object side, and a second lens which is a meniscus lens having a positive power whose convex surface faces the image surface side, wherein a condition expressed by the following expression is to be satisfied: 1.45≦(r3+r4)/(r3−r4)≦3.4, where, r3: center radius curvature of the object side face of the second lens, and r4: center radius curvature of the image surface side face of the second lens.