Patents by Inventor Christopher A. Hill

Christopher A. Hill 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).

  • Waveguide laser
    Patent number: 5684820
    Abstract: A waveguide laser (10) incorporates a guide (12) and two concave resonator mirrors (14, 16). The guide (12) is of square section with side (2a), and of length L equal to 4a.sup.2 /.lambda., where .lambda. is a laser operating wavelength. The mirrors (14, 16) are phase matched to respective Gaussian intensity profile radiation beams with beam waists at respective waveguide end apertures (20, 22). Each beam waist has a radius w.sub.0 in the range 0.1a to 0.65a to avoid waveguide edge effects and excitation of unwanted high order waveguide modes. The laser (10) has good transverse spatial mode characteristics.
    Type: Grant
    Filed: November 21, 1995
    Date of Patent: November 4, 1997
    Assignee: The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland of Defence and Evaluation Research Agency
    Inventors: Richard M. Jenkins, Christopher A. Hill
  • Fluid flow comingling jet
    Patent number: 4430780
    Abstract: A comingling jet having a body or housing through which a right cylindrical yarn chamber extends and an air entry orifice which intersects and communicates with the yarn chamber so that their axis are perpendicular to one another. An adjustable pin assembly is provided at the entry opening of the yarn chamber to modify the air flow characteristics of the yarn chamber.
    Type: Grant
    Filed: January 11, 1982
    Date of Patent: February 14, 1984
    Assignee: International Machinery Sales, Inc.
    Inventors: Stuart B. Sear, Christopher A. Hill