Patents by Inventor Harald Perthes

Harald Perthes 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: 4491391
    Abstract: A display device for displaying light characters against a dark background, particularly a liquid-crystal display. It has a fluid which can be switched between two optically different states located between two support plates (1, 2) which are parallel to each other. On one of the facing surfaces of the support plates there is applied an insulating layer of fixer which contains the spacer elements (7). The support plates (1, 2) are maintained at a given distance from each other by these spacers (7). Furthermore, a polarizer (11, 12) is associated with each support plate (1, 2). In order to assure a strong contrast between the character and its background with precise maintenance of the distance between the support plates (1, 2), the insulating layer of fixer completely covers the support plate (1) and the spacer elements (7) consist of a material of dark color.
    Type: Grant
    Filed: February 16, 1982
    Date of Patent: January 1, 1985
    Assignee: VDO Adolf Schindling AG
    Inventors: Friedrich W. Nickol, Harald Perthes