Patent ID: 8488258

Claim:
A lens system designed to provide a distorted image for relative illumination, comprising: an aperture stop; and a group of lenses in a fixed position along an optical axis, the group of lenses comprising: a first lens comprising a positive refractive power and a convex surface on an object side near an optical axis; a second lens comprising a negative refractive power and a meniscus shape in which a concave surface is on the object side near the optical axis; a third lens comprising a shape in which the convex surface is on the object side near the optical axis; a fourth lens comprising a shape in which the convex surface is on the object side near the optical axis; and a fifth lens comprising a small negative refractive power and a meniscus shape in which the concave surface is on the object side near the optical axis; wherein the aperture stop and the group of lenses are arranged along the optical axis in order from the object side; wherein at least one surface of the first lens is aspherical; wherein both surfaces of each of the second lens, the third lens, the fourth lens, and the fifth lens are aspherical; and wherein the first lens, the second lens, the third lens, the fourth lens, and the fifth lens are made of plastic.