Apparatus and method for transient thermal infrared spectrometry

Patent · Mon Dec 02 23:00:00 EST 1991

OSTI ID:868083

McClelland, John F ^[1]; Jones, Roger W ^[1]

---

1. Ames, IA

A method and apparatus for enabling analysis of a material (16, 42) by applying a cooling medium (20, 54) to cool a thin surface layer portion of the material and to transiently generate a temperature differential between the thin surface layer portion and the lower portion of the material sufficient to alter the thermal infrared emission spectrum of the material from the black-body thermal infrared emission spectrum of the material. The altered thermal infrared emission spectrum of the material is detected by a spectrometer/detector (28, 50) while the altered thermal infrared emission spectrum is sufficiently free of self-absorption by the material of the emitted infrared radiation. The detection is effected prior to the temperature differential propagating into the lower portion of the material to an extent such that the altered thermal infrared emission spectrum is no longer sufficiently free of self-absorption by the material of emitted infrared radiation, so that the detected altered thermal infrared emission spectrum is indicative of the characteristics relating to the molecular composition of the material.

• Research Organization: Ames Laboratory (AMES), Ames, IA; Iowa State University, Ames, IA (US)
• DOE Contract Number: W-7405-ENG-82
• Assignee: Iowa State University Research Foundation, Inc. (Ames, IA)
• Patent Number(s): US 5070242
• Application Number: 07/546,738
• OSTI ID: 868083
• Country of Publication: United States
• Language: English

Related Subjects

/250/
16
20
28
42
50
54
alter
altered
analysis
apparatus
applying
black-body
characteristics
characteristics relating
composition
cool
cooling
cooling medium
detected
detection
detector
differential
effected
emission
emission spectrum
emitted
emitted infrared
enabling
enabling analysis
extent
free
generate
indicative
infrared
infrared emission
infrared radiation
infrared spectrometry
layer
layer portion
material
material sufficient
medium
method
molecular
molecular composition
portion
prior
propagating
radiation
relating
self-absorption
spectrometer
spectrometry
spectrum
sufficient
sufficiently
sufficiently free
surface
surface layer
temperature
temperature differential
thermal
thermal infrared
transient
transient thermal
transiently
transiently generate