Patents by Inventor Michael S. Shumate

Michael S. Shumate 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).

  • Stark cell optoacoustic detection of constituent gases in sample
    Patent number: 4234258
    Abstract: An optoacoustic detector for gas analysis is implemented with Stark-effect cell modulation for switching a beam in and out of coincidence with a spectral line of a constituent gas in order to eliminate the heating effect of laser energy in the cell as a source of background noise. By using a multiline laser, and linearly sweeping the DC bias voltage while exciting the cell with a multiline laser, it is possible to obtain a spectrum from which to determine the combination of excited constituents and determine their concentrations in parts per million.
    Type: Grant
    Filed: August 31, 1978
    Date of Patent: November 18, 1980
    Inventors: Robert A. Administrator of the National Aeronautics and Space Administration, with respect to an invention of Frosch, Jack S. Margolis, Michael S. Shumate
  • Method and apparatus for Doppler frequency modulation of radiation
    Patent number: 4201468
    Abstract: A method and apparatus for frequency modulating radiation, such as from a laser, for optoacoustic detectors, interferometers, heterodyne spectrometers, and similar devices using two oppositely reciprocating cat's-eye retroreflectors to Doppler modulate the radiation. By reciprocally moving both retroreflectors, the center of mass is maintained constant to permit smooth operation at many Hertz. By slightly offsetting the axis of one retroreflector relative to the other, multiple passes of a light beam may be achieved for greater Doppler shifts with the same reciprocating motion of the retroreflectors. A Doppler shift of 2(v/c).nu. occurs for each pass where v is the velocity of each retroreflector, c is the speed of light, and .nu. is the frequency of radiation.
    Type: Grant
    Filed: November 3, 1978
    Date of Patent: May 6, 1980
    Assignee: California Institute of Technology
    Inventors: Jack S. Margolis, Daniel J. McCleese, Michael S. Shumate, Clay H. Seaman
  • Differential optoacoustic absorption detector
    Patent number: 4067653
    Abstract: A differential optoacoustic absorption detector employs two tapered cells in tandem or in parallel. When operating in tandem, two mirrors are used at one end remote from the source of the beam of light directed into one cell back through the other, and a lens to focus the light beam into the one cell at a principal focus half way between the reflecting mirror. Each cell is tapered to conform to the shape of the beam so that the volume of one is the same as for the other, and the volume of each receives maximum illumination. The axes of the cells are placed as close to each other as possible in order to connect a differential pressure detector to the cells with connecting passages of minimum length. An alternative arrangement employs a beam splitter and two lenses to operate the cells in parallel.
    Type: Grant
    Filed: August 27, 1976
    Date of Patent: January 10, 1978
    Inventors: James C. Administrator of the National Aeronautics and Space Administration, with respect to an invention of Fletcher, Michael S. Shumate