Patents by Inventor Albert A. Ballman

Albert A. Ballman 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).

  • Doped crystalline titanyl arsenates and preparation thereof
    Patent number: 5480569
    Abstract: Doped crystalline compositions (e.g., single domain crystals) of MTiOAsO.sub.4 (wherein M is K, Rb and/or Cs) are disclosed which contain at least about 10 ppm total of Fe, Sc and/or In dopant. Also disclosed is a flux process which is characterized by adding said dopant to a melt containing the components for forming MTiOAsO.sub.4, in an amount effective to provide a doped single domain crystal of MTiOAsO.sub.4 containing at least 10 ppm of said dopant.
    Type: Grant
    Filed: April 15, 1994
    Date of Patent: January 2, 1996
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Albert A. Ballman, Lap K. Cheng
  • Doped crystalline titanyl arsenates and preparation thereof
    Patent number: 5326423
    Abstract: Doped crystalline compositions (e.g., single domain crystals) of MTiOAsO.sub.4 (wherein M is K, Rb and/or Cs) are disclosed which contain at least about 10 ppm total of Fe, Sc and/or In dopant. Also disclosed is a flux process which is characterized by adding said dopant to a melt containing the components for forming MTiOAsO.sub.4, in an amount effective to provide a doped single domain crystal of MTiOAsO.sub.4 containing at least 10 ppm of said dopant.
    Type: Grant
    Filed: September 30, 1992
    Date of Patent: July 5, 1994
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Albert A. Ballman, Lap K. Cheng
  • Doped crystalline compositions and a method for preparation thereof
    Patent number: 5084206
    Abstract: A composition is disclosed which consists essentially of doped crystalline MTiOXO.sub.4 (wherein M is selected from the group consisting of K, Rb and Tl, X is selected from the group consisting of P and As) which contain at least about 100 ppm total of at least one dopant selected from the group consisting of Ga, Al and Si. The compositions generally have low ionic conductivity, and may be prepared using an improved flux process wherein Ga, Al and/or Si dopant is added to the flux in a total amount of at least about 0.5 mole % and the crystallization temperature is controlled to provide a crystalline composition containing the desired amount of dopant.
    Type: Grant
    Filed: February 2, 1990
    Date of Patent: January 28, 1992
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Albert A. Ballman, John D. Bierlein, August Ferretti, Thurman E. Gier, Patricia A. Morris
  • M.sub.1-x N.sub.x TiAs.sub.1-a P.sub.a O.sub.5 waveguides grown by liquid phase epitaxy and process of making same
    Patent number: 5039187
    Abstract: Optical waveguides prepared by liquid phase epitaxy comprising a film of M.sub.1-x N.sub.x TiAs.sub.1-a P.sub.a O.sub.5 on a substrate of MTiAs.sub.1-(a+b) O.sub.5 P.sub.(a+30 b) is disclosed.
    Type: Grant
    Filed: September 6, 1990
    Date of Patent: August 13, 1991
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Albert A. Ballman, Lap K. Cheng
  • Waveguiding epitaxial LiNbO.sub.3 films
    Patent number: 4073675
    Abstract: A process is described for making optical circuits on LiTaO.sub.3 substrates. The process involves putting down an epitaxial layer of LiNbO.sub.3 on the LiTaO.sub.3 substrates. Growth is preferably carried out on certain planes of the LiTaO.sub.3. These optical circuits are unique in that they are smooth, uniform in thickness and have a refractive index significantly larger than that of the substrate. This is advantageous in optical circuitry, since the optical modes in the circuits are quite distinct and can be coupled separately using such light sources as lasers and light emitting diodes.
    Type: Grant
    Filed: July 21, 1976
    Date of Patent: February 14, 1978
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Albert A. Ballman, Harold Brown, Raymond J. Martin, Ping K. Tien