Method and apparatus for millimeter-wave detection of thermal waves for materials evaluation
- Naperville, IL
- Downers Grove, IL
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.
- Research Organization:
- Argonne National Laboratory (ANL), Argonne, IL (United States)
- DOE Contract Number:
- W-31109-ENG-38
- Assignee:
- United States of America as represented by United States (Washington, DC)
- Patent Number(s):
- US 5020920
- OSTI ID:
- 867845
- Country of Publication:
- United States
- Language:
- English
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apparatus
millimeter-wave
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intensity
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heating
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oriented
narrow
spot
surface
material
radiation
volume
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scans
point-by-point
computer
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in-phase
quadrature
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alternatively
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array
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aperture
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heating source
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