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What the Heck is (Spectral) Emissivity?

February 10, 2010

Part One of Two from the mind of FLIR
It starts:
Fill two soda cans with hot water and wrap one with scotch tape. Which one will radiate more heat?
You might be surprised at the answer
(It has all to do with Spectral Emissivity, although this video continues the illusion that it’s really simple “Emissivity” at work! The [...]

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Spectral emissivity from 2 micrometers to 15 micrometers

April 6, 2008

Measurement of spectral emissivity from 2 micrometers to 15 micrometers
Charles D. Reid and E. D. McAlister
JOSA, Vol. 49, Issue 1, pp. 78- (1959)
Citation
C. D. Reid and E. D. McAlister, “Measurement of spectral emissivity from 2 micrometers to 15 micrometers,” J. Opt. Soc. Am. 49, 78- (1959)
http://www.opticsinfobase.org/abstract.cfm?URI=josa-49-1-78

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ET10 Reflectometer Measures Emissivity

March 21, 2008

San Diego CA, USA –Surface Optics’ ET10 measures emissivity values in two most commonly used spectral regions, 3 to 5 and 8 to 12 microns.
Its main application is to produce emissivity values for the infrared cameras.
Advanced IR cameras require the input of an emissivity value for accurate temperature calculations. The emissivity values obtained from tables [...]

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Spectral and Total Emissivity Measurement Services at Near Ambient Temperatures

September 1, 2007

The National Physical Laboratory in The UK offers a spectral emissivity measurment service (downloadable brochure – PDF 284kb) through its Infrared Optical Spectroscopy group to measure the spectral emissivity as needed by customers.
They also offer related calibration measurement services on their webpage as stated below:

“Optical Properties of Materials Measurement Service offers calibrations in the areas [...]

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Modifying a Surface To a Known Emissivity for Temperature Measurement

August 31, 2007

One of the techniques to deal with emissivity problems taught to most beginning Infrared Thermographers and many using so-called spot radiation thermometers or IR Thermometers, is to modify the surface with unknown spectral emissivity to one with a known emissivity. While much of that information seems to get lost in “How-To” books and notes, the [...]

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Radiometric Temperature: Concepts and Solutions

August 23, 2007

A downloadable (PDF Format) “Application Note” from the Santa Barbara Infrared website. It explains the relationship between emitted thermal radiation, reflected thermal radiation, emissivity and the wavelength region used by a measuring device. It provides several informative examples with figures and graphs.
It reads in part:
“.. a 40°C blackbody in a 40°C room would require no [...]

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