Patents by Inventor Michel Defrance

Michel Defrance 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).

  • Method of fabrication of non-linear control elements for a flat electrooptical display screen
    Patent number: 4732873
    Abstract: In a method of fabrication of non-linear control elements for a flat display screen of the liquid crystal type, successive layers of n.sup.30 doped amorphous semiconductor, of undoped amorphous semiconductor and of metal are deposited on a substrate, whereupon the control elements are formed by masking and etching. The flanks of the control elements are then isolated, whereupon the electrodes and control leads are formed by deposition and etching.
    Type: Grant
    Filed: March 31, 1986
    Date of Patent: March 22, 1988
    Assignee: Thomson-CSF
    Inventors: Jean N. Perbet, Bruno Mourey, Michel Graciet, Michel DeFrance, Patrick Truffer, Nicolas Szylo
  • Electrically controlled display device
    Patent number: 4525709
    Abstract: The invention relates to a screen with matrix access which makes use of a varistor as a switching element to control the orientation of the molecules forming a liquid crystal layer. The invention has as its object the elimination of the passive surfaces of the varistor substrate and their replacement by an insulating material having a low dielectric constant.
    Type: Grant
    Filed: August 23, 1982
    Date of Patent: June 25, 1985
    Assignee: Thomson-CSF
    Inventors: Michel Hareng, Jean-Noel Perbet, Michel Defrance