Patents by Inventor Andrew S. Keys

Andrew S. Keys 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).

  • Phase modulator with terahertz optical bandwidth formed by multi-layered dielectric stack
    Patent number: 6885779
    Abstract: An optical phase modulator includes a bandpass multilayer stack, formed by a plurality of dielectric layers, preferably of GaAs and AlAs, and having a transmission function related to the refractive index of the layers of the stack, for receiving an optical input signal to be phase modulated. A phase modulator device produces a nonmechanical change in the refractive index of each layer of the stack by, e.g., the injection of free carrier, to provide shifting of the transmission function so as to produce phase modulation of the optical input signal and to thereby produce a phase modulated output signal.
    Type: Grant
    Filed: June 6, 2001
    Date of Patent: April 26, 2005
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Andrew S. Keys, Richard L Fork
  • Phase modulator with terahertz optical bandwidth formed by multi-layered dielectric stack
    Publication number: 20030035610
    Abstract: An optical phase modulator includes a bandpass multilayer stack, formed by a plurality of dielectric layers, preferably of GaAs and AlAs, and having a transmission function related to the refractive index of the layers of the stack, for receiving an optical input signal to be phase modulated. A phase modulator device produces a nonmechanical change in the refractive index of each layer of the stack by, e.g., the injection of free carrier, to provide shifting of the transmission function so as to produce phase modulation of the optical input signal and to thereby produce a phase modulated output signal.
    Type: Application
    Filed: June 6, 2001
    Publication date: February 20, 2003
    Inventors: Andrew S. Keys, Richard L. Fork