Patents Examined by Digeo F. F. Gutierrez
  • Multi-wavelength optical thermometry
    Patent number: 5263776
    Abstract: Multi-wavelength optical thermometry provides for non-contact measurement of the temperature of a sample where the front surface and the back surface of the sample are used in a interferometer to measure changes in optical path length. Laser beams at two different wavelengths are used and the beam phase of the two resultant interference signals is used to unambiguously measure the path length change over a broad temperature range.
    Type: Grant
    Filed: September 25, 1992
    Date of Patent: November 23, 1993
    Assignee: International Business Machines Corporation
    Inventors: David W. Abraham, William M. Holber, Joseph S. Logan, Hemantha K. Wickramasinghe