主权项 |
1. An imaging lens comprising a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element arranged in order from an object side to an image side along an optical axis of said imaging lens, each of said first lens element, said second lens element, said third lens element, said fourth lens element, said fifth lens element and said sixth lens element having a refractive power, an object-side surface facing toward the object side, and an image-side surface facing toward the image side, wherein:
said object-side surface of said first lens element has a convex portion in a vicinity of the optical axis; said object-side surface of said second lens element has a concave portion in a vicinity of a periphery of said second lens element; said image-side surface of said third lens element has a convex portion in a vicinity of the optical axis; said image-side surface of said fourth lens element has a concave portion in a vicinity of the optical axis; said object-side surface of said fifth lens element has a concave portion in a vicinity of a periphery of said fifth lens element; said image-side surface of said sixth lens element is aspherical, and said sixth lens element is made of a plastic material; and said imaging lens satisfies ALT/T5≦5.00, where ALT represents a sum of thicknesses of said first lens element, said second lens element, said third lens element, said fourth lens element, said fifth lens element and said sixth lens element at the optical axis, and T5 represents the thickness of said fifth lens element at the optical axis. |