Decomposition of Fluorescent Illuminant Spectra for Accurate Colorimetry

Fluorescent lamps are widely used in the office environment and in common desktop scanners. These lamps are characterized by the nearly monochromatic emission lines present in their radiant spectrum. Due to the presence of spectral lines special care is required in the computation of tristimulus values under these illuminants. Accurate computation of the tristimulus values can be performed digitally by modeling the radiance as the sum of a continuous spectrum emitted by the phosphors and weighted impulses corresponding to the emission lines[2, 14, 3]. This paper considers a scheme for estimating the continuous spectrum and the strengths of the impulses from measurements of the spectrum with band limited sensors. The impact of noise in measured data on the accuracy of the final color computation is also considered.