Patent ID: 8305698

Claim:
An imaging lens consisting of: an aperture stop and a junction type compound lens wherein: a lens located on a side closest to an object is the junction type compound lens; the junction type compound lens comprising a first lens, a second and a third lens arranged in that order in a direction from the object side towards an image side; the second lens has both the surfaces on the object side and on the image side being made of flat-glass parallel plates; the first and third lenses are formed of curing resin; the first and second lenses are directly or indirectly bonded, the second and third lenses being also directly or indirectly bonded; the first lens is a plano-convex lens wherein the surface on the object side is a convex aspherical surface and the surface on the image side is a plane surface; and the third lens is aspherical in such a way that the surface on the object side is plane, while the surface thereof on the image side is convex at the position close to the optical axis and is concave on the periphery within the passing range of a light flux.