Patent ID: 9575288
Date: 2017-02-21
CPC Classifications: G02B

Claim:
1. An imaging lens which forms an image of an object on a solid-state image sensor, in which elements are arranged in order from an object side to an image side, comprising: an aperture stop; a first lens having positive refractive power and a convex surface near an optical axis on each of the object side and the image side; a second lens as a meniscus lens having negative refractive power and a concave surface on the image side; a third lens having positive refractive power and at least one aspheric surface; a fourth lens as a double-sided aspheric lens having positive refractive power; and a fifth lens as a double-sided aspheric lens having negative refractive power and a concave surface near an optical axis on each of the object side and the image side, the image-side surface of the fifth lens having a pole-change point in a position off the optical axis, wherein conditional expressions (1) to (3), (7) and (8) below are satisfied: where f: focal length of an overall optical system of the imaging lens f1: focal length of the first lens f3: focal length of the third lens r3: curvature radius of the object-side surface of the second lens r4: curvature radius of the image-side surface of the second lens νd3: Abbe number of the third lens at d-ray νd4: Abbe number of the fourth lens at d-ray νd5: Abbe number of the fifth lens at d-ray ih: maximum image height.