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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ASTM E307 – 72(2008) Standard Test Method for Normal Spectral Emittance

December 8, 2009

At Elevated Temperatures
Developed by ASTM Subcommittee: E21.04, on Space Simulation Test Methods, and in the Annual Book of ASTM Standards, Volume 15.0 Space Simulation; Aerospace and Aircraft; Composite Materials

Quoting from the standard’s Scope:
1. Scope
1.1 This test method describes a highly accurate technique for measuring the normal spectral emittance of electrically conducting materials or materials [...]

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Electro Optical Industries BB Emissivity Coatings

November 5, 2009

Electro Optical Industries (EOI) uses one of two high emissivity coatings on the surface of its blackbodies.
The EOI mid-temperature coating is used on both cavity and flat plate blackbodies that have a maximum operating temperatures of up to 210 °C.

Read the rest by visiting their webpage at: www.electro-optical.com/html/bb_rad/emissivity/emis_data.asp

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Blackbody Emissivity Primer

October 30, 2009

From the Electro-Optical Industries website:

“Effective emissivity is the ratio of the total amount of energy exiting a blackbody to that which is predicted by Planck’s law. This is the value most frequently referred to as “emissivity”. Effective emissivity of a cavity type blackbody will normally be much higher than the surface emissivity due to the [...]

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Measurements of Pool-Fire Temperature Using IR Technique. (419 K)

May 12, 2009

By Qian, C.; Saito, K.
Ref: Combustion Institute/Central and Western States (USA) and Combustion Institute/Mexican National Section and American Flame Research Committee. Combustion Fundamentals and Applications. Joint Technical Meeting. Proceedings. April 23-26, 1995, San Antonio, TX, Gore, J. P., Editor(s), 81-86 pp, 1995.
Sponsor: National Institute of Standards and Technology, Gaithersburg, MD
Abstract:
We made an attempt to measure [...]

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Table of Emissivities in Three Popular Spectral Regions

May 9, 2009

The Table of Emissivity on the INFRAPOINT Messtechnik GmbH website (Click here to visit) has summary data for a wide variety of materials broken down into three distinct spectral regions for the wavelength regions where the majority of infrared radiation thermometers and Infrared Thermal Imaging cameras operate.
First and second are tables that deal with the [...]

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Spectral emissivity of skin and pericardium

May 5, 2009

Spectral emissivity of skin and pericardium by J Steketee 1973 Phys. Med. Biol. 18 686-694 doi: 10.1088/0031-9155/18/5/307 Help
J Steketee, Department of Biological and Medical Physics, Erasmus University, Rotterdam, The Netherlands
Abstract.
A monochromator was modified to measure the emissivity, ?(?), of living tissue in the infrared region between 1 and 14 ?m. [...]

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Non-contact skin emissivity: measurement from reflectance

May 5, 2009

Reference Title:Non-contact skin emissivity: measurement from reflectance using step change in ambient radiation temperature Citation: T Togawa 1989 Clin. Phys. Physiol. Meas. 10 39-48 doi: 10.1088/0143-0815/10/1/004
Article by T Togawa of Inst. for Med. & Dental Eng., Tokyo Med. & Dental Univ., Japan
Abstract.
A method of estimating skin emissivity based on reflectance [...]

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Temporal variations in the apparent emissivity of various materials

March 4, 2009

Temporal variations in the apparent emissivity of various materials
Author: Salvaggio, C.; Miller, D.P.
Author URL: www.cis.rit.edu/~cnspci/publications/5425-29.pdf
Year: 2004
Abstract:
Spectral emissivity measurements gathered in the longwave infrared region of the spectrum during a recent airborne hyperspectral data collection experiment indicated that the spectral emissivity of certain organic polymers changed by as much as 10% throughout the day. Inorganic and [...]

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