Patent attributes
An imaging lens includes an aperture stop; a first lens having positive refractive power; a second lens having negative refractive power; a third lens; a fourth lens; a fifth lens having negative refractive power; and a sixth lens, arranged in this order from an object side to an image plane side. A surface of the first lens on the image plane side has a positive curvature radius. A surface of the third lens on the image plane side has a positive curvature radius. A surface of the fifth lens on the object side and a surface of the fifth lens on the image plane side have inflection points and are aspheric. A surface of the sixth lens on the object side has a positive curvature radius. The first to the third lenses have specific thicknesses so that specific conditional expressions are satisfied.
