Patent ID: 8149525

Claim:
An imaging lens of which a distortion aberration is corrected to be small enough that an absolute value of the distortion aberration is within 10.7%, comprising an aperture stop, and a junction type compound lens having a positive refractive power without containing a diffractive optical element, wherein said aperture stop and said junction type compound lens are arranged in this sequence from an object side to an image side, said junction type compound lens comprises a first lens, a second lens and a third lens arranged in this sequence from the object side to the image side, said first lens and said third lens are formed of a curable resin material, said second lens is formed of a glass material, said first lens and said second lens are directly bonded, and said second lens and said third lens are directly bonded, said second lens is a plane parallel glass plate, said first lens is a plano-convex lens where the object side face of said first lens is a convex surface facing the object side, said third lens is a plano-convex lens where the image side face of said third lens is a convex surface facing the image side, and the following conditions (1)-(4) are satisfied, 0 ≦|N 3 −N 2 |≦0.0968 (1) 0 ≦|N 3 −N 4 |≦0.0968 (2) 0≦|ν 3 −ν 2 |≦30.0 (3) 0≦|ν 3 −ν 4 |≦30.0 (4) where N 2 : refractive index of said first lens N 3 : refractive index of said second lens N 4 : refractive index of said third lens ν 2 : Abbe number of said first lens ν 3 : Abbe number of said second lens ν 4 : Abbe number of said third lens.