Patent ID: 7538958
Filing Date: 2009-05-26
Classification: G02B

Abstract:
1. A wide-angle lens comprising, in order from an object side to an image side, a first lens element of negative refractive power, a second lens element of positive refractive power, a third lens element of positive refractive power and a cemented doublet element of positive refractive power consisting of a fourth lens element and a fifth lens element joined together, the first lens element having an object-side aspheric surface, the second lens element being of a meniscus lens and having an object-side concave surface and an image-side convex surface at least one of which is an aspheric surface, the third lens element being of a meniscus lens and having an object-side concave surface and an image-side convex surface at least one of which is an aspheric surface, wherein the second, third, fourth and fifth lens elements satisfy the following condition: where f2345 represents a combined focal length of the second, third, fourth and fifth lens elements and f represents a total focal length of the wide-angle lens.