Establishment of illuminance scale at UME with an accurately calibrated radiometer

Traceability in illuminance measurements at the National Metrology Institute of Turkey (TUBITAK-UME) was established in 2003 with a detector-based realization. The new measurement technique was developed for the determination of illuminance responsivity and upgrating of the illuminance scale. The unit of the illuminance responsivity, in A/1x, was measured with an expanded uncertainty of 0.2% (k = 2) by supplying using the developed scanning technique for the calculation of color correction factor. The surface of a radiometer was scanned using a double-monochromator facility upgraded with an x-y scanning system. The illuminance responsivity as a function of bandpass and temperature were also investigated in this study.