Infinite large-aperture lens system with aspherical surfaces

摘要

A large-aperture lens system with a lens having aspherical surfaces to be used to read out optical information and to be used in optical communication transmission systems or the like. The lens in the system has a large aperture despite its very small focal length, because it is manufactured using glass with both a high refractive index and a high Abbe number giving the lens excellent aberration characteristics. The system can be manufactured using ultra-precision press-molding technology.