Patents by Inventor Johannes K. A. Boesten

Johannes K. A. Boesten has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4397669
    Abstract: A method for the manufacture of a mould intended for the precision moulding of glass articles, notably aspherical lenses. The desired shape and dimensional accuracy are imparted to a mechanically treated preform by an accurate polishing operation. Subsequently, the polished preform is prestressed and reinforced by a chemothermal treatment. The surface of the mould thus obtained comprises an edge zone which is subject to compressive stress and which changes over, via a neutral stress-free zone, to the core which is subject to tensile stress. The mould in accordance with the invention has a longer life and produces moulded products having a quality which is higher than that of products made by means of known moulds.
    Type: Grant
    Filed: January 18, 1982
    Date of Patent: August 9, 1983
    Assignee: U.S. Philips Corporation
    Inventors: Jan Haisma, Johannes K. A. Boesten, Henderikus deVroome