Patent ID: 7262925

Claim:
An image lens array, from object side to image side, comprising: a first lens, a second lens, and a third lens; wherein the first lens with positive refracting power has a front convex surface and a back concave surface, a radius of curvature of the front convex surface and that of the back concave surface of the first lens are: L 1 R 1 and L 1 R 2 that satisfy an equation as: L 1 R 1 /L 1 R 2 <0.5, the first lens is provided with aspherical surface; an aperture is arranged behind the first lens, for controlling brightness of the image lens array; the second lens having a front concave surface and a back convex surface, is located behind the aperture and has a negative refracting power, and the second lens is also provided with aspherical surface; and the third lens with a front convex surface and a back concave surface, is located behind the second lens and has a positive power, a radius of curvature of the front convex surface and that of the back concave surface of the third lens are: L 3 R 1 and L 3 R 2 that satisfy an equation as: R 3 R 1 /L 3 R 2 >0.3, the third lens is provided with aspherical surface; focal lengths of the first, second and third lenses are: f1, f2 and f3, and a focal length of the image lens array is f, these four focal lengths are controlled to satisfy the following conditions: 1.5 > f/f 1 >1.0 1.2 > f/f 2 >0.7 1.2 > f/f 3 >0.3.