Patents by Inventor Christopher Edward Jeffree

Christopher Edward Jeffree 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 laser marking a body of material having a thermal conductivity approximately equal to that of glass
    Patent number: 5767483
    Abstract: A method of providing a body of material (14), having a thermal conductivity approximately equal to that of glass, with a sub-surface mark. A beam of laser radiation (12) to which the material (14) is substantially opaque is directed to surface of the body, so as to cause beam energy to be aborbed at the surface of the material in an amount sufficient to produce localised stresses within the body (14) at a location spaced from the surface without any detectable change at the surface, the localised stresses thus produced being normally invisible to the naked eye but capable of being rendered visible under polarised light.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: June 16, 1998
    Assignee: United Distillers PLC
    Inventors: Allan Cameron, Mary Violet Stockdale, Robert Marc Clement, Neville Richard Ledger, Christopher Edward Jeffree