Spectral Power Distribution of Cathode-Ray Phosphors

This paper embodies some of the results of a study undertaken because of the lack of substantial agreement among colorimetric determinations made from cathode-ray-tube screens by television manufacturers in the United States. The ICI (International Commission on Illumination) system of color specification is described, and is applied to the visible light produced by cathode-ray screens. A survey was made of the principal colorimetric methods now in use by television manufacturers. These methods have been evaluated in terms of how closely their inherent characteristics meet the criteria of the 1931 ICI Standard Observer. The necessity for standardization of colorimetric measuring equipment is pointed out. Suggestions are offered as to the manner in which such standardization might be achieved.