Parr, A.
(2001),
The Candela and Photometric and Radiometric Measurements, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD
(Accessed April 19, 2024)
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The Candela and Photometric and Radiometric Measurements
Published
Author(s)
Abstract
The national measurement system for photometric and radiometric quantities is presently based upon techniques and a measurement chain that make these quantities traceable to a high accuracy cryogenic radiometer. The redefinition of the candela in 1979 provided the opportunity for national measurement laboratories to base their photometric measurements on optical detector technology rather than on the emission from high temperature blackbody optical sources. The ensuing technical developments of the past 20 years, including the significant improvements in cryogenic radiometer performance, have provided the opportunity to place the fundamental maintenance of most photometric and radiometric quantities upon absolute detector based technology as was envisioned by the 1979 redefinition. This paper will review the status of the NIST implementation of the technical changes mandated by the 1979 redefinition of the candela and its effect upon the maintenance and dissemination of optical radiation measurements.Citation
Journal of Research (NIST JRES) -
Volume
106 No. 1
NIST Pub Series
Pub Type
NIST Pubs
Keywords
laser power, photometry, radiation temperature, radiometric, standards
Citation
Created January 1, 2001, Updated February 17, 2017