Patents by Inventor Randall C. Wentross

Randall C. Wentross 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).

  • Multi-source reactive deposition process for the preparation of blue light emitting phosphor layers for AC TFEL devices
    Patent number: 5505986
    Abstract: A multi-source reactive deposition process for preparing a phosphor layer for an AC TFEL device having the chemical formula M.sup.II M.sup.III.sub.2 X.sub.4 :RE, where M.sup.II is a group II metal taken from the group magnesium, calcium, strontium and barium, M.sup.III is a group III metal taken from the group aluminum, gallium and indium, X is taken from the group sulfur and selenium, and RE comprises a rare earth activator dopant taken from the group cerium and europium is disclosed. The phosphor film is formed in crystalline form on a substrate heated to a temperature between 400.degree. and 800.degree. C. by depositing more than one deposition source chemical where at least one of the deposition source chemicals of the group II metal or the group III metal is a compound.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: April 9, 1996
    Assignee: Planar Systems, Inc.
    Inventors: Karl-Otto Velthaus, Reiner H. Mauch, T. Achim Oberacker, Hans-Werner Schock, Sey-Shing Sun, Randall C. Wentross, Richard T. Tuenge