WIDE-ANGLE IMAGE TAKING LENS SYSTEM

摘要

A wide-angle image taking lens system includes an aperture stop and an optical assembly including: in order from an object side to an image side: first, second, third, fourth and fifth lens elements, the system has a total of five lens elements with refractive power, wherein Abbe numbers of the first and fifth lens element are V1, V5, a distance along an optical axis between the first and second lens element is T12, a central thickness of the first lens element is CT1, focal lengths of the system, second and third lens elements are f, f2, f3, maximum effective diameters of an object-side surface of the first lens element and an image-side surface of the fifth lens element are CA11, CA52, satisfying: 1.5

主权项

1. A wide-angle image taking lens system comprising an aperture stop and an optical assembly, the optical assembly comprising: in order from an object side to an image side:
a first lens element with a negative refractive power having an aspheric object-side surface and an aspheric image-side surface; a second lens element with a positive refractive power having an object-side surface being convex near an optical axis, the object-side and an image-side surfaces of the second lens element being aspheric, the second lens element being made of plastic material; a third lens element with a refractive power having an aspheric object-side surface and an aspheric image-side surface, the third lens element being made of plastic material; a fourth lens element with a positive refractive power having an image-side surface being convex near an optical axis, an object-side and the image-side surfaces of the fourth lens element being aspheric, the fourth lens element being made of plastic material; a fifth lens element with a negative refractive power having an image-side surface being concave near an optical axis, an object-side and the image-side surfaces of the fifth lens element being aspheric, the fifth lens element being made of plastic material, more than one inflection point being formed on the image-side surface of the fifth lens element; wherein an Abbe number of the first lens element is V1, an Abbe number of the fifth lens element is V5, a distance along the optical axis between the first lens element and the second lens element is T12, a central thickness of the first lens element is CT1, a focal length of the wide-angle image taking lens system is f, a focal length of the second lens element is f2, a focal length of the third lens element is f3, a maximum effective diameter of the object-side surface of the first lens element is CA11, a maximum effective diameter of the image-side surface of the fifth lens element is CA52, and the following conditions are satisfied:
1.5