Patent ID: 8643957
Filing Date: 2014-02-04
Classification: G02B

Abstract:
1. An optical image system comprising, in order from an object side to an image side: a first lens element with positive refractive power having a convex object-side surface; second lens element with refractive power; a third lens element with positive refractive power having at least one of an object-side surface and an image-side surface being aspheric; a fourth lens element with refractive power having a concave object-side surface and a convex image-side surface, wherein at least one of the object-side surface and the image-side surface of the fourth lens element is aspheric; a fifth lens element with positive refractive power having a convex image-side surface; and a sixth lens element with negative refractive power having a concave image-side surface, wherein the sixth lens element is made of plastic material and has at least one of an object-side surface and the image-side surface being aspheric, and the image-side surface of the sixth lens element changes from concave at a paraxial region to convex at a peripheral region; wherein a focal length of the optical image system is f, a focal length of the first lens element is f1, a focal length of the second lens element is f2, a focal length of the third lens element is f3, and the following relationships are satisfied: