The Birth of a Bifocal Ultex K by Continental Optical Company - 1950

Continental Optical Company, 1950 No date. Appears to have been published in the 1950's. Folio, 14 1/2"x11 1/2". White textured Cloth. Fine. Pages held together with internal metal spiral binding. 32pp. Profusely illustrated with dramatic b/w period industrial photographs, charts, some in color. Illustrates factories where lenses are made, technical aspects of lens design, etc. John Isaac Hawkins, the inventor of trifocal lenses, coined the term bifocals in 1824 and credited Benjamin Franklin. In 1955, Irving Rips of Younger Optics created the first seamless or "invisible" bifocal, a precursor to all progressive lenses. This followed Howard D. Beach's 1946 work in "blended lenses", O'Conner's "Ultex" lens in 1910, and Isaac Schnaitmann's single-piece bifocal lens in 1837.. 1st Edition. Hardcover. Fine.