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Illuminance responsivity calibration of reference photometers at the NIST SIRCUS and SCF facilities



George P. Eppeldauer, Carl C. Miller, Thomas C. Larason, Yoshihiro Ohno


The illuminance responsivities of two transfer standard photometers have been directly determined from their spectral responsivity calibrations at two different calibration facilities of NIST. The main characteristics of the two photometers, and their calibrations are described. The spectral and broad-band (illuminance) responsivities measured at the two different facilities are compared. The two different illuminance responsivity determinations on both photometers agreed within 0.1 % with an overall uncertainty of 0.2 % (k=2). A new photometric scale derivation scheme is also discussed.
Proceedings Title
CIE Midterm Conference on Light and Lighting
Conference Dates
May 27-29, 2009
Conference Location
Budapest, -1


calibration, illuminance responsivity, photometry, spectral responsivity
Created May 29, 2009, Updated February 19, 2017