Patent ID: 8570670
Filing Date: 2013-10-29
Classification: G02B

Abstract:
1. An imaging lens comprising: a first lens having negative refractive power; a second lens having negative refractive power; a third lens having positive refractive power; a fourth lens having negative refractive power; and a fifth lens having positive refractive power, arranged in this order from an object side to an image plane side, wherein said first lens is formed in a shape so that a curvature radius of a surface thereof on the image plane side is positive, said second lens is formed in a shape so that a surface thereof on an object side has a sharp convex surface facing the object side from an optical axis to an periphery, and a curvature radius of a surface thereof on the image plane side is positive, said third lens is formed in a shape so that a curvature radius of a surface thereof on the object side is positive and a curvature radius of a surface thereof on the image plane side is negative, said fourth lens is formed in a shape so that a curvature radius of a surface thereof on the object side is negative and a curvature radius of a surface thereof on the image plane side is positive, and said fifth lens is formed in a shape so that a curvature radius of a surface thereof on the object side is positive and a curvature radius of a surface thereof on the image plane side is negative, and the surface thereof on the image plane side is formed in an aspheric surface having an inflection point.