Patents by Inventor Paul M. Alt

Paul M. Alt 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: 4845482
    Abstract: The elimination of crosstalk between data lines and pixel cells in a thin film transistor/liquid crystal display is accomplished by applying a data signal to a given data line for a time period less than the standard scan line period of the display, and applying a crosstalk compensation signal to the given data line for the remainder of the scan line period.
    Type: Grant
    Filed: October 30, 1987
    Date of Patent: July 4, 1989
    Assignee: International Business Machines Corporation
    Inventors: Webster E. Howard, Paul M. Alt
  • Patent number: 4819038
    Abstract: An array of thin film transistor (TFT) devices is provided with a conductive region, such as a strip, for temporarily coupling a floating pel eletrode of each of the plurality of TFT devices to a conductor on an underlying substrate. The conductor may be a row or column metalization line associated with an adjacent row or column of the array. The conductive strip may therefore be utilized, in conjunction with appropriate voltage potentials and test circuitry, to test each of the TFT devices prior to the final fabrication of the TFT array into a completed flat panel display. Thus, nonfunctioning or out of specification arrays may be identified at an early point in the manufacturing cycle of the display. The strip may be comprised of amorphous silicon which is illuminated during the test in order to reduce the intrinsic resistance of the strip. The strip may also be comprised of a layer of metalization, which layer is removed from the array at the completion of the test.
    Type: Grant
    Filed: December 22, 1986
    Date of Patent: April 4, 1989
    Assignee: IBM Corporation
    Inventor: Paul M. Alt
  • Patent number: 4221002
    Abstract: It has been discovered for the practice of this disclosure that there is a threshold for switching with light an AC coupled electroluminescence (EL) device within the .DELTA.V of the luminance-voltage hysteresis loop thereof. Practice of this disclosure provides hybrid matrix-addressing of an electroluminescence display device with memory through luminance-voltage hysteresis by "ANDING" electrical and optical signals. It has particular utility for a large aspect ratio display, e.g., a single line display, i.e., one for which there is more information content in one direction than in another direction.
    Type: Grant
    Filed: November 6, 1978
    Date of Patent: September 2, 1980
    Assignee: International Business Machines Corporation
    Inventors: Paul M. Alt, Omesh Sahni