Patents by Inventor Harry S. Hoffman, Jr.

Harry S. Hoffman, Jr. 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: 4683470
    Abstract: An a.c. Plasma Display Panel is operated in a scanning mode using a conventional video data stream such as that applied to a cathode ray tube display terminal. A full line write followed by a selective erase technique is employed for image generation on a line by line basis. By eliminating the non-selective write signal used in normal plasma display operation, the duration of the sustain signal is substantially decreased and the write, erase and sustain functions are provided at a nominal 40KC rate.
    Type: Grant
    Filed: March 5, 1985
    Date of Patent: July 28, 1987
    Assignee: International Business Machines Corporation
    Inventors: Tony N. Criscimagna, Harry S. Hoffman, Jr., William R. Knecht
  • Patent number: 4622549
    Abstract: Operation of an AC plasma display panel requires the three control operations of write, erase, and sustain. Sustain, write and erase signals are stored in a plurality of sections in a storage device and the sections are selectively accessed according to the specific operation to be provided to the plasma panel display. The control signals stored within a given sequence are selected so that no dimming occurs during write and erase operations. A brightness control is provided to modulate the average repetition rate of signals applied to the plasma display panel. In this manner, a plurality of flicker-free brightness levels may be chosen.
    Type: Grant
    Filed: June 29, 1983
    Date of Patent: November 11, 1986
    Assignee: International Business Machines Corporation
    Inventors: Tony N. Criscimagna, Harry S. Hoffman, Jr., Thomas J. Milich
  • Patent number: 4611203
    Abstract: An A.C. Plasma Display Panel is operated in a video mode using the same signal train as applied to a conventional cathode ray tube terminal. For character generation, a selective erase technique is employed in which all cells in a raster line are discharged and then selectively erased in accordance with the video data to be displayed. To facilitate the erase operation, a line of cells in close proximity to the scan line being selectively erased is employed to provide adequate and uniform priming for the erase operation, and is synchronized to maintain its position with respect to the line being erased. A short plasma erase signal is utilized to fit within the scan rate of the display. The invention is also applicable to character generation in block or multi-line mode.
    Type: Grant
    Filed: March 19, 1984
    Date of Patent: September 9, 1986
    Assignee: International Business Machines Corporation
    Inventors: Tony N. Criscimagna, Harry S. Hoffman, Jr., William R. Knecht
  • Patent number: 4525707
    Abstract: A gas panel can provide optical data readout in an essentially serial manner for copying, communication, interaction and indication. This is accomplished by using substitute sustain cycles for reading particular addresses. A complement sustain signal obtained through the address selection circuitry is superimposed on a partial sustain signal to produce the substitute sustain signal. This provides a complete sustain cycle for the selected address(es) only. Flashes of light at the addressed positions indicate storage of logical "1s" at such addresses.
    Type: Grant
    Filed: December 31, 1981
    Date of Patent: June 25, 1985
    Assignee: International Business Machines Corporation
    Inventors: Harry S. Hoffman, Jr., Donald R. Thompson, Luther L. Zimmerman