Patents by Inventor Theodorus H. M. van den Berk

Theodorus H. M. van den Berk 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: 4536059
    Abstract: In a matrix display device using the bistability effect of cholesteric liquid crystals, two supporting plates are provided with first and second pluralities of ridges. The electrodes of the liquid crystal extend across the second ridges onto the first ridges on which a separation strip separates the electrodes from one another. Liquid crystal orienting layers are provided over the entire surface of the supporting plate. The second ridges lying between the first ridges divide each picture element of the display into many sub-elements. Accordingly, the formation of focal-conical texture because of surface inhomogenities in the picture element display will be restricted to a single sub-element as a result of the homeotropic-nematic texture at the edges of the sub-element.
    Type: Grant
    Filed: December 27, 1982
    Date of Patent: August 20, 1985
    Assignee: U.S. Philips Corporation
    Inventor: Theodorus H. M. van den Berk