Patents by Inventor Charles C. Ih

Charles C. Ih 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: 4880286
    Abstract: A method of producing an IR hologram having a planar surface on which a fringe pattern is recorded, the fringe pattern being produced by interference with a visible wavelength on the surface of reconstruction from a computer generated hologram.
    Type: Grant
    Filed: October 19, 1987
    Date of Patent: November 14, 1989
    Assignee: University of Delaware
    Inventor: Charles C. Ih
  • Patent number: 4775972
    Abstract: A method and associated system for providing multi-channel transmission of digital and broadband video information in optical fiber communication for local area networks through frequency-division-multiplexing, comprising the steps of generating a plurality of closely spaced optical carrier wave pairs with the optical carrier waves within each optical carrier wave pair having a predetermined separation frequency between one another, assigning each of the plurality of optical carrier wave pairs to a predetermined frequency slot and optically combining the plurality of optical carrier wave pairs to provide a multiplexed optical output wave. Advantageously, in addition to direct detection the plurality of optical carrier wave pairs may be detected by opto-electronic heterodyne detection and/or incoherent optical-heterodyne detection to electronically recover the optical carrier wave pairs.
    Type: Grant
    Filed: May 10, 1985
    Date of Patent: October 4, 1988
    Assignee: ITT Corporation, Defense Communications Division
    Inventors: Charles C. Ih, Charles K. Kao
  • Patent number: 4768852
    Abstract: Method and apparatus for frequency domain modulation optical fiber communication particularly useful for digital and analog signal transmission comprising, in the order recited, a plurality of parallel-connected signal input units each incorporating individual laser sources provided with means modulating the output radiations of said laser sources responsive to individual signal inputs, thereby establishing, for each signal input, an individual optical information wave train, a collimating lens, an acousto-optical modulator means introducing a sub-carrier signal developing a beat frequency with said optical information wave train, an optical fiber coupler transmitting the resulting signal through an optical fiber to a common square law detector and an information receiver isolating a preselected individual signal input according to its associated individual sub-carrier frequency, said individual sub-carrier frequencies being spaced one from another by a frequency interval forestalling interference in the rece
    Type: Grant
    Filed: November 27, 1985
    Date of Patent: September 6, 1988
    Assignee: University of Delaware
    Inventor: Charles C. Ih
  • Patent number: 4726011
    Abstract: The method and associated system for providing increased information carrying capacity in optical fiber communication through frequency-division-multiplexing, comprising the steps of generating a reference optical beam, generating a plurality of closely spaced optical carriers having frequencies which are coherently related to the reference frequency of the reference optical beam and which are capable of drifting with the reference frequency while maintaining coherence therewith, and combining the plurality of closely spaced optical carriers to provide a multiplexed optical output beam.
    Type: Grant
    Filed: April 8, 1985
    Date of Patent: February 16, 1988
    Assignee: ITT Defense Communications, a division of ITT Corporation
    Inventors: Charles C. Ih, Charles K. Kao
  • Patent number: 4579417
    Abstract: Method and apparatus for frequency domain modulation optical fiber communication particularly useful for digital and analog signal transmission comprising, in the order recited, a plurality of parallel-connected signal input units each incorporating individual laser sources provided with means modulating the output radiations of said laser sources responsive to individual signal inputs, thereby establishing, for each signal input, an individual optical information wave train, a collimating lens, an acousto-optical modulator means introducing a sub-carrier signal developing a beat frequency with said optical information wave train, an optical fiber coupler transmitting the resulting signal through an optical fiber to a common square law detector and an information receiver isolating a preselected individual signal input according to its associated individual sub-carrier frequency, said individual sub-carrier frequencies being spaced one from another by an interval forestalling interference in the reception of
    Type: Grant
    Filed: January 28, 1983
    Date of Patent: April 1, 1986
    Assignee: University of Delaware
    Inventor: Charles C. Ih
  • Patent number: 4210803
    Abstract: Method and apparatus for signal transmission via an optical fiber transmission line comprising providing a first substantially monochromatic beam of radiation reserved as a carrier radiation beam, providing a second substantially monochromatic beam of radiation of preselected different frequency than the first substantially monochromatic beam of radiation frequency-interlocked with the first beam of radiation to a preselected degree dependent upon the transmission service to be effected reserved as an information radiation beam, imposing an electrical signal to be transmitted upon the information radiation beam, thereby responsively modulating the information radiation beam, combining the carrier radiation beam and the modulated information radiation beam, transmitting the combined radiation via the optical fiber transmission line to a preselected destination, and detecting the combined radiation with a square law detector to thereby obtain a subcarrier signal constituting the difference in frequency between
    Type: Grant
    Filed: March 15, 1979
    Date of Patent: July 1, 1980
    Assignee: University of Delaware
    Inventor: Charles C. Ih
  • Patent number: 4155630
    Abstract: A process and apparatus for improving image creation in a coherent light imagery system which involves directing diffused laser light onto a mirror having a rocking motion that will cause the reflected rays to sweep a two-dimensional area and focusing the reflected light through a diffuser before collimating same for use in image creation. More particularly, this invention creates the rocking motion by applying a combination of voltages to three independent piezo-electric crystals upon which the mirror is mounted.
    Type: Grant
    Filed: November 17, 1977
    Date of Patent: May 22, 1979
    Assignee: University of Delaware
    Inventor: Charles C. Ih