The definitive primer for non-contact plastic film temperature measurement by Ircon, Inc., Niles, Il, USA in a downloadable PDF format (556 Kb).
This Note has been a unique resource for IR temperature measurements in the thin film plastic film processing industry for more than 20 years. It was recently removed from the Ircon web page on plastics application, but the link to the Fluke website download seems to work.
(If you didn’t know, Fluke bought Ircon a few years ago.)
In any event the link, above may not function and you might have to revert to the original Ircon webpage at: ircon.com/web/sol_ind/plas.php.
(Seems that some web designers and managers forget that there are legacy links to resources on older web pages that have value. We wish they would exercise the common courtesy of placing a redirect and notice of a resource link change, but then we wish for lot of things that only thoughtful, rational people do, and we aren’t always kind or rational at times ourselves.)
There was also a link to the same download recently on the Fluke Instruments website at: support.fluke.com/ircon-sales/Download/Asset/3310192_6127_ENG_C_W.PDF. It might or might not work and if it doesn’t, try back at the original web page.
The applications note describes the critical factors to be evaluated when selecting the proper instrument. It includes transmission curves for most common plastic films from which spectral emissivity estimates can be made.
More detailed or higher resolution measurements are usually recommended for specific products, but this is still an excellent summary of the key properties of a range of popular materials.
We expect to be asking companies for permission to house such useful resource documents here, but do not hold out much hope. But then agai, nothing ventured, nothing gained. Even if only one organization agrees, it will be a bonus for everyone, we think.
ICESS is located on the University of California, Santa Barbara campus.
It provides an environment in which Earth and computer science are strongly coupled. Their focus is on research and graduate education in Earth sciences, with emphasis on processes governing the environmental optics of the Earth.
Data available includes 24 sample of vegetation ranging from the Leaf of the Algerian Ivy (Hedera canariensis algerian ivy) to the Leaf of Sweet Gum tree (liquidamber styreciflua), one sample of bark of the Eucalyptus tree and three sample of dry grass.
Commentary of the site data reads:
“Vegetation Green vegetation typically has a very high emissivity because it is structured and contains water. Senescent (dry) vegetation has a more variable emissivity, especially in the 3 to 5 µm region, which depends on the type and structure of the cover type, the dryness, and so forth.”
Data is provided on: 9 samples of Nebraska Soil Lab, 14 samples of Oklahoma Soil, 10 samples of Death Valley, CA Soil, 10 samples of Railroad Valley, Nevada playa Soil, 2 samples of Railroad Valley, NV soil powder, 6 samples of Koehn, CA, 3 samples of Concord MA Soil, 9 samples of Page Arizona Sandy Soil, 2 samples of Goleta , CA Beach Sand, 3 samples of Soil – Prepared by ICESS, and more.
Commentary of the data reads:
“Soil and Sands exhibit stronger spectral features than many others. The “restralen” bands of quartz sand cause strong spectral features between 8 and 10 microns that depend on the grain size. The signature in the 3 to 5 µm region depends strongly on the water and organic content. The dryer, purer soils have lower emissivities in this region.”
From the MODIS (Moderate Resolution Imaging Spectrometer) UCSB Emissivity Library. Includes four sample for Water, three for Seawater, three for Ice and two for snow.
Commentary on the data on the site read, in part:
“Water, ice, and snow generally have a high emissivity, 0.94 to 0.99, across the thermal infrared region. Snow is unusual in that it has a high reflectance in the solar (visible) region where most of the downwelling energy is during the day, and a very high emissivity in the thermal region.”