Patent ID: 7995293

Claim:
An image pickup lens comprising, in order from an object side thereof: a first lens block with a positive power, comprising a first lens substrate being a parallel flat plate, a lens portion 1 a with a positive power, formed on an object-side surface of the first lens substrate, an object-side surface of the lens portion 1 a being a convex surface facing the object side, and a lens portion 1 b with a negative power, formed on an image-side surface of the first lens substrate, an image-side surface of the lens portion 1 b being a concave surface facing an image side; and a second lens block comprising a second lens substrate being a parallel flat plate, and a lens portion 2 a with a negative power, formed on an object-side surface of the second lens substrate, an object-side surface of the lens portion 2 a being a concave surface facing the object side, wherein the image pickup lens satisfies the following expressions: 0.6<fl/ f< 1.0, 0.00< |n 1 a−n 1 s| <0.06, 0.00< |n 1 b−n 1 s|< 0.06, 0.00≦ |n 1 a−n 1 b|< 0.05, and 10< v 1 a−v 2 a< 45, where fl is a focal length of the first lens block at d-line, f is a focal length of a total system of the image pickup lens at d-line, n 1 a is a refractive index of the lens portion 1 a at d-line, n 1 b is a refractive index of the lens portion 1 b at d-line, n 1 s is a refractive index of the first lens substrate, v 1 a is an Abbe number of the lens portion 1 a, and v 2 a is an Abbe number of the lens portion 2 a.