Patents by Inventor Jonathan P. Kettlewell

Jonathan P. Kettlewell 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).

  • Thermal imager
    Patent number: 5021657
    Abstract: A thermal imager employs an intermediate field stop (8) which is preferably placed at an intermediate image plane (P) in front of a cryogenically cooled detector (1) mounted on a substrate (2). Radiation gathered by a telescope is directed onto the detector through an aperture (9) in the field stop. The field stop limits the rays which are emitted by the detector and substrate and which are subsequently retro-reflected back to the detector (called narcissus rays).
    Type: Grant
    Filed: May 15, 1989
    Date of Patent: June 4, 1991
    Assignee: GEC - Marconi Limited
    Inventors: Jonathan P. Kettlewell, Brian F. Smith