Patent ID: 8988795
Filing Date: 2015-03-24
Classification: G02B

Abstract:
1. An optical imaging lens comprising, from an object side to an image side: a first lens element; a second lens element; a third lens element; and a fourth lens element, wherein each of the first lens element, the second lens element, the third lens element, and the fourth lens element have an object-side surface facing toward the object side and an image-side surface facing toward the image side, wherein: the first lens element has a positive refracting power, the object-side surface of the first lens element has a convex portion in a vicinity of an optical axis and a convex portion near a circumference of the first lens element, and the image-side surface of the first lens element has a convex portion in a vicinity of the optical axis and a convex portion near the circumference of the first lens element; the second lens element has a negative refracting power, the object-side surface of the second lens element has a concave portion in a vicinity of the optical axis and a concave portion near a circumference of the second lens element, and the image-side surface of the second lens element has a concave portion in a vicinity of the optical axis; the third lens element has a positive refracting power, the object-side surface of the third lens element has a concave portion in a vicinity of the optical axis, and the image-side surface of the third lens element has a convex portion in a vicinity of the optical axis; the fourth lens element has a negative refracting power and the image-side surface of the fourth lens element has a concave portion in a vicinity of the optical axis and a convex portion near a circumference of the fourth lens element; the optical imaging lens has only four lens elements having a refracting power; and the optical imaging lens satisfies the following relations: 0.430≦AG12/AG23≦1.303, wherein AG12 is a width of an air gap between the first and second lens elements along the optical axis and AG23 is a width of an air gap between the second and third lens elements along the optical axis.