Patent ID: 8630047
Filing Date: 2014-01-14
Classification: G02B,H01L

Abstract:
1. An imaging lens, comprising: a first lens having positive refractive power; a second lens having negative refractive power; and a third lens having positive refractive power arranged in the order from an object side to an image plane side, wherein said first lens has a shape so that a curvature radius of a surface thereof on the object side and a curvature radius of a surface thereof on the image plane side are both positive, said second lens has 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, said third lens has a shape so that a curvature radius of a surface thereof on the object side and a curvature radius of a surface thereof on the image plane side are both positive, said first lens has a focal length f said second lens has a focal length f said third lens has a focal length f said first lens and said second lens have a composite focal length f said second lens and said third lens have a composite focal length f