Patents by Inventor Hsuan S. Chen

Hsuan S. 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: 5347376
    Abstract: A method and apparatus for making a holographic shadowgram of an object are disclosed. The method and apparatus include a light source for generating and expanding a coherent light beam. The method and apparatus also include a reflector for reflecting the coherent light beam to simultaneously produce a diffuse object beam and a coherent reference beam such that differential vibration between the object and reference beams is substantially eliminated, and for illuminating the object with the object beam and creating an interference pattern between the object and reference beams. The method and apparatus further include a recorder for recording the interference pattern to produce the holographic shadowgram.
    Type: Grant
    Filed: February 5, 1993
    Date of Patent: September 13, 1994
    Assignee: Saginaw Valley State University
    Inventors: Hsuan S. Chen, Gregory A. Wright
  • Patent number: 5299035
    Abstract: An image of an object embedded in a diffusing medium is formed by propagating a coherent or equivalent light pulse through the diffusing medium and applying a reference pulse so as to gate precisely the first emerging light transmitted through the diffusing medium. An ultra-short pulse, having a duration on the order of 150 fs, insures that only the first emerging light is used to form a hologram. Instability in the diffusing medium, which may be inherent therein, as is the case with living tissue, or artificially induced therein, such as by vibrating the specimen, ensures that a subsequent hologram has a different background noise and speckle pattern. Integration of such holograms causes the background noise to average out, but time-invariant features, such as the object being imaged, become increasingly more visible as more holograms are integrated.
    Type: Grant
    Filed: March 25, 1992
    Date of Patent: March 29, 1994
    Assignee: University of Michigan
    Inventors: Emmett N. Leith, David S. Dilworth, Hsuan S. Chen, Ye Chen, Joaquin L. Lopez, Janis A. Valdmanis
  • Patent number: 4850662
    Abstract: A HOE for use in a wavelength .lambda..sub.3 is made by recording a holographic corrector plate at a wavelength of .lambda..sub.1. The HOE is then recorded at a wavelength .lambda..sub.2. Aberration caused by differences between the wavelength of recording and the wavelength of HOE usage is compensated for by inserting the holographic corrector plate in one of the beams in used in recording the HOE.
    Type: Grant
    Filed: February 12, 1988
    Date of Patent: July 25, 1989
    Assignee: Saginaw Valley State University
    Inventor: Hsuan S. Chen
  • Patent number: 4783133
    Abstract: Provided is a systemic approach to creating a hologram from a sequential series of two dimensional transparencies each having a differing viewpoint of a scene taken simultaneously by a camera in incoherent light and a projection apparatus using coherent light in combination with said transparencies to form a rainbow hologram of the scene originally photographed. The invention utilizes a lenticular lens array to provide parallax information and a perpendicularly oriented cylindrical lens for focusing, along with additional optical enhancing elements, to obtain high quality rainbow holograms from scenes originally photographed in natural light.
    Type: Grant
    Filed: August 26, 1986
    Date of Patent: November 8, 1988
    Assignee: Saginaw Valley State University
    Inventor: Hsuan S. Chen