IMAGE SENSOR

PURPOSE:To miniaturize a lens set for image formation and the whole of an optical system without damaging the image formation performance of the optical system by performing a cutting or a molded working for the lens shape of a lens diameter in a non-optical axis symmetrical shape. CONSTITUTION:In a lens set 1 for image formation, two sheets of aspheric surface lenses 1a and 1b are arranged serially to an optical axis (r) within a lens fixing frame 1c. The lenses 1a and 1b are manufactured by performing a pressure injection molding for acrylic resin. The lens fixing frame 1c is manufactured by injection-molding a light-shielding engineering plastic material. The lens 1a on the side of the object of the lens set 1 has a symmetrical shape to the optical axis r and the effective diameter A becomes the opening diameter of the lens set 1. The shape of the lens 1b on the side of an image is formed into a shape where up and down parts of an axially symmetrical lens are cut in parallel with an x-direction, keeping a prescribed distance from the optical axis (r).