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Radiation thermometers and blackbodies can be calibrated using a set of blackbodies. These blackbodies can vary in size and can be fixed-points of the ITS-90 or
NIST has established an absolute aperture area measurement facility for circular and near-circular apertures use in radiometric instruments. The facility
In 1993, the United States Congress directed the U.S. Department of Transportation to establish "a standard for a minimum level of retroreflectivity that must
FASCAL 2 facility is solely dedicated to spectral irradiance scale realizations and calibrations. The spectral irradiance standards are calibrated using a high
The FASCAL has been in continuous operations since 1970s for the calibrations of spectral radiance of sources. The measurements are performed by the use of a
The NIST gonio-spectroradiometer is used to measure total spectral radiant flux (TSRF) of incandescent lamps. The instrument consists of a 3-axis scanning
Visible to near-infrared spectral comparator facility (Vis/NIR SCF) The Vis/NIR SCF is a monochromator-based system that typically measures the spectral power
Solid-state lighting (SSL) is increasingly being introduced into the market and it is expected that many of the light sources currently used for general