IMAGING LENS

摘要

A compact low-cost imaging lens with an F-value of 2.5 or less which achieves both low-profileness and a wide field of view and corrects various aberrations properly. It includes elements arranged from an object side to an image side as follows: a first lens with positive refractive power having a convex object-side surface; a second lens with negative refractive power having a concave object-side surface; a third lens with positive refractive power having convex object-side and image-side surfaces and having at least one aspheric surface; a fourth lens with positive refractive power as a double-sided aspheric lens having a convex image-side surface; and a fifth lens with negative refractive power as a double-sided aspheric lens having a concave image-side surface. The imaging lens satisfies a conditional expression 20<νd1−νd2<50, where νd1 denotes Abbe number of the first lens at d-ray, and νd2 denotes Abbe number of the second lens at d-ray.

主权项

1. An imaging lens which forms an image of an object on a solid-state image sensor and includes elements arranged in order from an object side to an image side, comprising:
a first lens with positive refractive power having a convex surface on the object side; a second lens with negative refractive power having a concave surface on the object side; a third lens with positive refractive power having a convex surface on each of the object side and the image side and having at least one aspheric surface; a fourth lens with positive refractive power as a double-sided aspheric lens having a convex surface on the image side; and a fifth lens with negative refractive power as a double-sided aspheric lens having a concave surface on the image side, wherein a conditional expression (1) below is satisfied:
20<νd1−νd2<50  (1) where νd1: Abbe number of the first lens at d-ray, and νd2: Abbe number of the second lens at d-ray.