Patents by Inventor Opher Berkman

Opher Berkman 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: 5200853
    Abstract: The invention provides a durable multipurpose screenboard especially adapted for both the screening of projected images and for writing thereon, wherein the screenboard comprises an upper section, a core section and a base section, the upper section comprising at least two superposed layers of transparent overlay sheets, each of the sheets weighing between 20 and 120 grams per square meter and having been soaked in a solution or melt of a polymeric resin material to subsequently form an intermediate solid plastic layer, the upper surface of the upper sheet being roughened by a plurality of closely-spaced complementary depressions of depth between 0.01 mm and 0.
    Type: Grant
    Filed: February 24, 1992
    Date of Patent: April 6, 1993
    Inventor: Opher Berkman