Patents by Inventor Shobha Singh

Shobha Singh 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: 4297005
    Abstract: Display devices are described which contain, in addition to organic quinones and suitable organic solvent, a solid ionic conductor. Such display devices are advantageous because of exceptional persistence of the display. Thus, an image may be retained without application of electrical energy. In addition, these displays exhibit high optical contrast and low power consumption. Under certain conditions, these devices are non-linear (exhibit sharp thresholds) which permit multiplexing. This is highly advantageous in display device applications.
    Type: Grant
    Filed: June 25, 1979
    Date of Patent: October 27, 1981
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: David W. Johnson, Jr., Shobha Singh, LeGrand G. Van Uitert, George J. Zydzik
  • Patent number: 4245883
    Abstract: Electrically activated components such as switches, modulators, attenuators, and mode selectors are disclosed which can be used in networks of waveguides in optical communications systems. Disclosed components comprise an electrochromic medium in combination with a suitable ion source and means for producing a variable electric field across the medium. A change of color in the medium in response to variation of the electric field strength is instrumental in influencing direction and intensity of light propagating in a network.
    Type: Grant
    Filed: December 26, 1978
    Date of Patent: January 20, 1981
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Leo F. Johnson, Shobha Singh, LeGrand G. Van Uitert
  • Patent number: 4240717
    Abstract: An electrodeposition display device is described which uses an electrolyte containing silver species and certain anion species including iodide bromide or chloride. The electrolyte also contains a substituted ammonium halide such as tetrabutyl ammonium iodide. Such display devices have high contrast, large viewing angle and rapid redissolution of the display.
    Type: Grant
    Filed: December 26, 1978
    Date of Patent: December 23, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Irfan Camlibel, Shobha Singh, LeGrand G. Van Uitert, George J. Zydzik
  • Patent number: 4240716
    Abstract: An electrodeposition display device is described which uses an electrolyte containing silver species and certain anion species including iodide and bromide. The electrolyte also contains an opacifier made up of solid semiconductor substance and solid insulator substance. Such display devices have high contrast, large viewing angle and a pleasing variety of colors including blue, red and brown.
    Type: Grant
    Filed: December 15, 1978
    Date of Patent: December 23, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Irfan Camlibel, Shobha Singh, LeGrand G. Van Uitert, George J. Zydzik
  • Patent number: 4240693
    Abstract: Electrically activated optical switches, couplers, and modulators are disclosed which can be incorporated in waveguide networks in optical communications systems. Disclosed devices comprise an electroplating medium in combination with a suitable source of an electric field whose strength can be varied to cause transition of the electroplating medium between plated and unplated states. Changes of reflectivity and refractive index are the bases of switching and coupling applications, respectively.
    Type: Grant
    Filed: December 26, 1978
    Date of Patent: December 23, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Leo F. Johnson, Shobha Singh, LeGrand G. Van Uitert
  • Patent number: 4187530
    Abstract: Certain structures are described for solid state electrical switches which employ electrochromic material. These structures involve use of a common base contact for both switching and readout circuits. The structures are particularly easy to fabricate using integrated circuit techniques and exhibit reduced electrical shorts due to reduced migration of metallic ions.
    Type: Grant
    Filed: June 1, 1978
    Date of Patent: February 5, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Shobha Singh, LeGrand G. Van Uitert, George J. Zydzik
  • Patent number: 4163982
    Abstract: A solid state electrical switch is described which exhibits high off/on resistance ratios and low insertion loss. An additional advantage is that removal of the switching energy does not alter the status (off or on) of the switch. The active solid state material in the switch is an electrochromic material (e.g., tungsten trioxide) which undergoes a transformation from insulator to metallic conductor on injection of certain ions.
    Type: Grant
    Filed: April 29, 1977
    Date of Patent: August 7, 1979
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Mauro Di Domenico, Jr., Shobha Singh, Legrand G. Van Uitert
  • Patent number: 4146309
    Abstract: A process is described for producing devices with gold films on surfaces composed of certain inorganic fluoride compounds. An adhesion compound such as lead fluoride, cadmium fluoride or tin fluoride or mixtures of these compounds is interspersed between inorganic fluoride surface and gold film. This process is particularly attractive for the fabrication of electrochromic display devices and solid-state switches. This procedure insures good adhesion of gold film to inorganic fluoride and insures high reliability in the manufacture of such devices. In addition, electrodes made in accordance with the invention have highly desirable electrical characteristics including ohmic resistance characteristics and low electrode resistances.
    Type: Grant
    Filed: March 10, 1978
    Date of Patent: March 27, 1979
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Shobha Singh, LeGrand G. Van Uitert, George J. Zydzik