Patent ID: 7433135

Claim:
An image pick-up lens system comprising: a first lens with positive refractive power comprising a convex first surface and a convex second surface; a second lens with negative refractive power comprising a concave third surface and a convex fourth surface; a third lens with positive refractive power comprising a convex fifth surface and a convex sixth surface; and a fourth lens with negative refractive power comprising a concave seventh surface and a concave eighth surface; wherein the first lens, the second lens, the third lens and the fourth lens are aligned in that order from an object side to an image side, and each of the four lenses is an aspheric lens made from a plastic material, the first surface, the second surface, the third surface, the fourth surface, the fifth surface, the sixth surface, the seventh surface and the eighth surface are aligned in that order from the object side to the image side, and each of the surfaces is aspheric.