Patents by Inventor John T. Fischer

John T. Fischer 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).

  • Display device drive circuit
    Patent number: 4766430
    Abstract: A drive circuit for a liquid crystal display includes a counter for each column of the display. The counters are set with brightness counts to establish the grey scales for the pixels. The counters turn transfer gates on when a count is present and off when the count is zero. An analog generator biases the columns through the transfer gates so that each column is biased to a level determined by the brightness count of the respective counter.
    Type: Grant
    Filed: December 19, 1986
    Date of Patent: August 23, 1988
    Assignee: General Electric Company
    Inventors: Glynn G. Gillette, Roger G. Stewart, John T. Fischer
  • System for correcting for color impurities due to horizontal beam landing errors in flat panel display devices
    Patent number: 4749918
    Abstract: A flat panel display device is divided into channels and includes deflection electrodes for scanning electron beams horizontally across the channels. Convergence electrodes are voltage biased to converge the electron beams at points along the transverse line scanned by the electron beams. A compensation voltage generator provides compensation voltages to compensate for horizontal landing errors of the electron beams.
    Type: Grant
    Filed: December 8, 1981
    Date of Patent: June 7, 1988
    Assignee: RCA Licensing Corporation
    Inventor: John T. Fischer
  • System for applying grey scale codes to the pixels of a display device
    Patent number: 4742346
    Abstract: A system for applying grey scale codes to a display device having a plurality of columns of pixels, has a segmented shift register, with one shift register segment for each pixel column. Data stored in the shift register segments are transferred to counters through multiplex circuitry. The counters control transfer gates by which voltages are applied to the pixel columns.
    Type: Grant
    Filed: December 19, 1986
    Date of Patent: May 3, 1988
    Assignee: RCA Corporation
    Inventors: Glynn G. Gillette, Roger G. Stewart, John T. Fischer