主权项 |
1. An optical imaging lens, sequentially from an object side to an image side along an optical axis, comprising an aperture stop, first, second, third, fourth, fifth and sixth lens elements, each of said first, second, third, fourth, fifth and sixth lens elements having refracting power, an object-side surface facing toward the object side and an image-side surface facing toward the image side and a central thickness defined along the optical axis, wherein:
said first lens element has positive refracting power, said image-side surface of said first lens comprises a convex portion in a vicinity of the optical axis; said second lens element is constructed by plastic material; said image-side surface of said third lens element comprises a convex portion in a vicinity of the optical axis; said image-side surface of said fourth lens element comprises a convex portion in a vicinity of the optical axis; said object-side surface of said fifth lens element comprises a concave portion in a vicinity of the optical axis; said image-side surface of said sixth lens element which is constructed by plastic material comprises a concave portion in a vicinity of the optical axis; the central thickness of said fourth lens element is represented by T4, an air gap between said fourth lens element and said fifth lens element along the optical axis is represented by G45, and T4 and G45 satisfy the equation: T4/G45≦2.8; said optical imaging lens comprises no other lenses having refracting power beyond said six lens element; wherein an air gap between said second lens element and said third lens element along the optical axis is represented by G23, an air gap between said fifth lens element and said sixth lens element along the optical axis is represented by G56, and G23 and G56 satisfy the equation:
G23/G56≦10. |