Patents by Inventor Wallace W. Chen

Wallace W. Chen 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).

  • Patent number: 5416332
    Abstract: An improved wide-spectrum test target assembly, with visual and near IR (infrared) targets integrated with a long wavelength emissivity target. A single relatively thick optical fiber (78) is used to receive target signals emitting from several thinner fibers (72, 74, 76), each carrying a signal of different wavelength. The integrated signal is then relayed to an aperture (108) of an emissivity target through a gradient index lens (88) to further combine with the long wavelength target signal emitted from the emissivity target assembly (100). By selecting appropriate numerical apertures and diameters of the fibers, relatively high power output is achieved. A light collimator (200) is also disclosed for collimating light generated by the test target assembly to simulate targets at infinity.
    Type: Grant
    Filed: October 1, 1993
    Date of Patent: May 16, 1995
    Assignee: Hughes Aircraft Company
    Inventors: Wallace W. Chen, I-Fu Shih
  • Patent number: 5324937
    Abstract: An improved target for testing and calibrating a detection device. The target (10) includes a metal substrate (12) with a first layer (14) of high emissivity material and a second layer (16) of low emissivity material are deposited thereon. In the specific implementation, the substrate (12) is copper, the first layer (14) is chromium-oxide and the second layer (16) is chrome. In the illustrative embodiment, an aperture (22) is drilled through the substrate (12) and the first and second layers (14, 16) thereon. An infrared emitter (20) is located at the aperture (22) to provide point source radiation. A conventional heater (26) is applied to the back surface of the target. A pattern is etched on second layer (16) on the front surface of the target using electron beam lithography. The use of a metal substrate (12) allows for the drilling of small holes more easily than in the conventional target.
    Type: Grant
    Filed: January 21, 1993
    Date of Patent: June 28, 1994
    Assignee: Hughes Aircraft Company
    Inventors: Wallace W. Chen, I-Fu Shih