Patents by Inventor Ian P. Llewellyn

Ian P. Llewellyn 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).

  • Pulsed plasma apparatus and process
    Patent number: 4935661
    Abstract: An apparatus for pulsed plasma treatment of a substrate surface includes means for removing spent gas from a region adjacent the substrate for each pulse. The apparatus may also include means for sweeping an intense plasma region across a substrate surface. Rapid gas exchange is provided by pressure pulsing the gas admission. This facility also provides means for rapidly alternating different gases.
    Type: Grant
    Filed: June 26, 1986
    Date of Patent: June 19, 1990
    Assignee: STC plc
    Inventors: Rudolf A. Heinecke, Sureshchandra M. Ojha, Ian P. Llewellyn
  • Pulsed plasma process for treating a substrate
    Patent number: 4824690
    Abstract: In a pulsed radio frequency plasma deposition process the pulse repetition frequency is matched to the gas exchange rate. This is achieved by using a pulse width of 50 to 500 microseconds and a pulse repetition rate corresponding to the time within which gas is exchanged in the reaction region.
    Type: Grant
    Filed: November 3, 1987
    Date of Patent: April 25, 1989
    Assignee: Standard Telephones and Cables Public Limited Company
    Inventors: Rudolf A. H. Heinecke, Suresh M. Ojha, Ian P. Llewellyn
  • Method of surface treatment
    Patent number: 4749589
    Abstract: In a pulsed plasma process for surface treatment of a substrate the containing reactor vessel (11) has an inner cross-section conforming to the substrate geometry so as to confine the intense plasma region to the substrate surface (12). Preferably this region should be within 15 to 20 mm of the surface. Advantageously the inner surface is provided by a demountable insert (13).
    Type: Grant
    Filed: December 10, 1985
    Date of Patent: June 7, 1988
    Assignee: STC plc
    Inventors: Rudolf A. H. Heinecke, Sureshchandra M. Ojha, Ian P. Llewellyn
  • Surface treatment of plastics material
    Patent number: 4684535
    Abstract: Discontinuities, e.g. scratches, in a plastics surface are removed by exposing the surface to a pulsed radio frequency plasma comprising a mixture of argon and hydrogen. After melting has been effected the surface is exposed to an argon plasma to effect cross-linking to form a smooth surface layer.
    Type: Grant
    Filed: July 28, 1986
    Date of Patent: August 4, 1987
    Assignee: Standard Telephones & Cables
    Inventors: Rudolf A. H. Heinecke, Suresh M. Ojha, Ian P. Llewellyn