Method and apparatus for millimeter-wave detection of thermal waves for materials evaluation
Abstract
A method and apparatus for generating thermal waves in a sample and for measuring thermal inhomogeneities at subsurface levels using millimeter-wave radiometry. An intensity modulated heating source is oriented toward a narrow spot on the surface of a material sample and thermal radiation in a narrow volume of material around the spot is monitored using a millimeter-wave radiometer; the radiometer scans the sample point-by-point and a computer stores and displays in-phase and quadrature phase components of thermal radiations for each point on the scan. Alternatively, an intensity modulated heating source is oriented toward a relatively large surface area in a material sample and variations in thermal radiation within the full field of an antenna array are obtained using an aperture synthesis radiometer technique.
- Inventors:
-
- Naperville, IL
- Downers Grove, IL
- Issue Date:
- Research Org.:
- Argonne National Laboratory (ANL), Argonne, IL (United States)
- OSTI Identifier:
- 867845
- Patent Number(s):
- 5020920
- Assignee:
- United States of America as represented by United States (Washington, DC)
- Patent Classifications (CPCs):
-
G - PHYSICS G01 - MEASURING G01K - MEASURING TEMPERATURE
G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- DOE Contract Number:
- W-31109-ENG-38
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- method; apparatus; millimeter-wave; detection; thermal; waves; materials; evaluation; generating; sample; measuring; inhomogeneities; subsurface; levels; radiometry; intensity; modulated; heating; source; oriented; narrow; spot; surface; material; radiation; volume; monitored; radiometer; scans; point-by-point; computer; stores; displays; in-phase; quadrature; phase; components; radiations; scan; alternatively; relatively; variations; field; antenna; array; obtained; aperture; synthesis; technique; intensity modulated; quadrature phase; thermal radiation; material sample; phase components; heating source; millimeter-wave radio; wave detection; thermal waves; phase component; surface level; wave radio; /374/324/342/343/
Citation Formats
Gopalsami, Nachappa, and Raptis, Apostolos C. Method and apparatus for millimeter-wave detection of thermal waves for materials evaluation. United States: N. p., 1991.
Web.
Gopalsami, Nachappa, & Raptis, Apostolos C. Method and apparatus for millimeter-wave detection of thermal waves for materials evaluation. United States.
Gopalsami, Nachappa, and Raptis, Apostolos C. Tue .
"Method and apparatus for millimeter-wave detection of thermal waves for materials evaluation". United States. https://www.osti.gov/servlets/purl/867845.
@article{osti_867845,
title = {Method and apparatus for millimeter-wave detection of thermal waves for materials evaluation},
author = {Gopalsami, Nachappa and Raptis, Apostolos C},
abstractNote = {A method and apparatus for generating thermal waves in a sample and for measuring thermal inhomogeneities at subsurface levels using millimeter-wave radiometry. An intensity modulated heating source is oriented toward a narrow spot on the surface of a material sample and thermal radiation in a narrow volume of material around the spot is monitored using a millimeter-wave radiometer; the radiometer scans the sample point-by-point and a computer stores and displays in-phase and quadrature phase components of thermal radiations for each point on the scan. Alternatively, an intensity modulated heating source is oriented toward a relatively large surface area in a material sample and variations in thermal radiation within the full field of an antenna array are obtained using an aperture synthesis radiometer technique.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 1991},
month = {Tue Jan 01 00:00:00 EST 1991}
}