Patents by Inventor Gary D. Boyd

Gary D. Boyd 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: 4717243
    Abstract: Threshold electric fields required to achieve high speed matrix addressing of selected cells in a bistable nematic liquid crystal storage display are reduced by employing a short duration, priming pulse signal in accordance with the principles of the invention. The short priming pulse signal applied to a selected cell modifies the binding energy for disclinations attached to sites of orientational discontinuity, thereby changing the threshold field required for electrical switching between bistable states. Threshold reduction also depends on the AC frequency and duration of a writing pulse signal applied to the selected cell subsequent to the priming pulse signal.
    Type: Grant
    Filed: March 21, 1986
    Date of Patent: January 5, 1988
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Gary D. Boyd, Julian Cheng
  • Patent number: 4601543
    Abstract: A bistable nematic liquid crystal display cell is switched between topologically equivalent, asymmetric horizontal states. Switching is initiated by application of a directional, symmetry breaking field such as a transverse magnetic field. An electric potential is then applied across the cell to complete the switching cycle and maintain the state. The cell includes upper and lower parallel substrates, upper and lower topographically textured tilt alignment surfaces on the corresponding substrates, and nematic liquid crystal material between the substrates. In an active region of the cell, the tilt alignment surfaces form an equal reverse tilt boundary condition. In an isolation region surrounding the active region of the cell, the tilt alignment surfaces form a parallel tilt boundary condition.
    Type: Grant
    Filed: October 17, 1985
    Date of Patent: July 22, 1986
    Assignee: AT&T Bell Laboratories
    Inventors: Gary D. Boyd, Julian Cheng, Robert B. Meyer, Robert N. Thurston
  • Patent number: 4472026
    Abstract: A row and column matrix of strip electrodes is utilized for switching bistable liquid crystal display cells from the vertical state to the horizontal state via resistive heating by applying an electric current of sufficient magnitude and duration to selected electrodes. Resistive heating causes the liquid crystal to undergo a phase transition from the nematic mesophase to an isotropic phase. Extinction of the current permits the liquid crystal to cool preferentially into the horizontal state of the nematic mesophase. Horizontal-to-vertical state switching is performed by conventional electric field effect techniques.
    Type: Grant
    Filed: May 6, 1982
    Date of Patent: September 18, 1984
    Assignee: AT&T Bell Laboratories
    Inventors: Gary D. Boyd, Julian Cheng
  • Patent number: 4430601
    Abstract: An AC plasma panel display (100) is described with selective row and column shifting capability. The column conductors (C.sub.2, C.sub.4 . . . , C.sub.512) are common between a staging area (11) and an exhibiting area (12) while the other column conductors (C.sub.1, C.sub.3 . . . , C.sub.511) are terminated at the boundary between the two areas. The row shifting is accomplished in the staging area to enter display data on the panel. Column shifting is used between the two areas to transport display data onto the exhibiting area from the staging area. The modified display panel requires a minimum number of drivers and intrinsically isolates column and row shifting during operation.
    Type: Grant
    Filed: April 5, 1982
    Date of Patent: February 7, 1984
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Gary D. Boyd, Peter D. T. Ngo
  • Patent number: 4333708
    Abstract: A liquid crystal cell having memory is provided by disposing a liquid crystal material having nematic directors between two substrates which are fabricated to contain an array of singular points. The cell may further include means for detaching singularities such as appropriate electrode arrangements.These substrate configurations provide multistable configurations of the director alignments because disclinations must be moved, either through the bulk of the liquid crystal material or on the substrate surfaces to switch between the stable configurations.The switching of the device between stable configurations may be accomplished by the application of electrical fields to the liquid crystal material.The stable configurations may be optically differentiated by the incorporation of pleochroic dyes into the liquid crystal material or by crossed polarizers.
    Type: Grant
    Filed: November 30, 1979
    Date of Patent: June 8, 1982
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Gary D. Boyd, Julian Cheng, Peter D. T. Ngo
  • Patent number: 4309267
    Abstract: An rf sputter etch or reactive sputter etch apparatus which can be used for etching substrates at oblique angles utilizes a cathode formed from a metal grid and an equipotential enclosure. The substrate is supported in the enclosure either parallel to or at an oblique angle to the surface of the grid.
    Type: Grant
    Filed: July 21, 1980
    Date of Patent: January 5, 1982
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Gary D. Boyd, Larry A. Coldren, Frederick G. Storz
  • Patent number: 4298250
    Abstract: Solid state electrochromic devices are fabricated using, as the electrochromic material, ionic conductors such as heteropoly acids. The properties of the ionic conductors permit construction of a device having only two electrodes and the electrochromic material. In operation, low voltages impressed between the electrodes induce a color change. For example, when phosphotungstic acid is employed, the color change is from white to dark blue. Cycle times as low as 100 msec are achievable and the devices exhibit memory properties.
    Type: Grant
    Filed: October 31, 1978
    Date of Patent: November 3, 1981
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Gary D. Boyd, Sarat K. Mohapatra, Benjamin Tell, Sigurd Wagner, Fred Wudl
  • Patent number: 4225216
    Abstract: Disclosed is an electro-optical device in which color changes are electrically induced in an electrochromic material which is a single or polycrystalline niobium tungstate represented approximately by the formula W.sub.9 Nb.sub.8 O.sub.47. The device comprises an ion source and a source of an electrical field which may be reversible so as to produce coloring and bleaching of the electrochromic material. Due to high corrosion resistance of such material, the ion source may conveniently be a hydrous electrolyte.
    Type: Grant
    Filed: February 21, 1979
    Date of Patent: September 30, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Gary D. Boyd, Ross A. Lemons, James C. Phillips, Joseph P. Remeika, Edward G. Spencer
  • Patent number: D352328
    Type: Grant
    Filed: March 1, 1993
    Date of Patent: November 8, 1994
    Inventor: Gary D. Boyd