A detector-based absolute scale for spectral irradiance in the 380–900-nm wavelength region has been developed and tested at the Helsinki University of Technology (HUT). Derivation of the scale and its use for photometric and colorimetric measurements are described. A thorough characterization of a filter radiometer, constructed from a reflection trap detector, a precision aperture, and a set of seven temperature-controlled bandpass filters, is presented. A detailed uncertainty analysis of the scale indicates a relative standard uncertainty of approximately 0.2% throughout most of the wavelength region. The standard uncertainties obtained in measurements of correlated color temperature and luminous intensity of three Osram Wi41/G tungsten–halogen lamps are 2 K and 0.3%, respectively. The spectral irradiance scale is compared with the HUT luminous intensity scale. The agreement of the results at the 0.1% level is well within the combined standard uncertainty of the two scales.
© 1997 Optical Society of America
Petri Kärhä, Pasi Toivanen, Farshid Manoochehri, and Erkki Ikonen, "Development of a detector-based absolute spectral irradiance scale in the 380-900-nm spectral range," Appl. Opt. 36, 8909-8918 (1997)