The spectral energy distribution of daylight

A series of measurements, extending over a year, was made at Enfield, Middlesex, using a grating monochromator to determine the spectral energy distribution of daylight between 3000 and 8000 A, particularly of total sky radiation without direct sunlight. The results are considered with respect to the structure of the curves, their equivalent chromaticities and the related full radiator distributions. Average distributions are given for several daylight sources including those at the limits of the usual range of chromaticities used in colour matching. From these, specifications for real or artificial daylight at any intermediate colour temperature can be set up. The values so obtained are more realistic than the theoretical data of the Abbot-Gibson formulation.

[1]  D. B. Judd.  A Maxwell Triangle Yielding Uniform Chromaticity Scales , 1935 .

[2]  Deane B. Judd.  Estimation of Chromaticity Differences and Nearest Color Temperature on the Standard 1931 ICI Colorimetric Coordinate System , 1936 .

[3]  E. Pettit.  No. 622. Spectral energy-curve of the sun in the ultraviolet. , 1940 .

[4]  Parry Moon,et al.  Proposed standard solar-radiation curves for engineering use , 1940 .

[5]  A. H. Taylor,et al.  The Distribution of Energy in the Visible Spectrum of Daylight , 1941 .

[6]  R. Stair.  Ultraviolet spectral distribution of radiant energy from the sun , 1951 .

[7]  R. Stair.  Ultraviolet Radiant Energy From the Sun Observed At 11,190 Feet , 1952 .

[8]  Yoshio Tanaka,et al.  Absorption Coefficient of Ozone in the Ultraviolet and Visible Regions , 1953 .

[9]  R. Stair,et al.  Ultraviolet spectral radiant energy reflected from the Moon , 1953 .

[10]  R. Stair,et al.  Spectral distribution of energy from the sun , 1954 .

[11]  W. E. Knowles Middleton,et al.  The Color of the Overcast Sky , 1954 .

[12]  Z. Sekera,et al.  Global Radiation Resulting from Multiple Scattering in a Rayleigh Atmosphere , 1954 .

[13]  R. Stair,et al.  Preliminary spectroradiometric measurements of solar constant , 1956 .

[14]  D. L. Macadam.  Continuously Recording Spectroradiometer , 1958 .

[15]  R. Scolnik,et al.  Solar Spectral Irradiance and Vertical Atmospheric Attenuation in the Visible and Ultraviolet , 1959 .

[16]  Measurement of Color Rendering Tolerances , 1959 .

[17]  Dorothy Nickerson.  Light Sources and Color Rendering , 1960 .

[18]  R. G. Schmitt,et al.  Ultraviolet Spectral Energy Distributions of Natural Sunlight and Accelerated Test Light Sources , 1960 .

[19]  Some Spectral Irradiance Measurements of Upwelling Natural Light off the East Coast of the United States , 1961 .

[20]  G. Wyszecki,et al.  Color of daylight from the north sky , 1963 .

[21]  Kenneth L. Kelly,et al.  Lines of Constant Correlated Color Temperature Based on MacAdam’s (u,υ) Uniform Chromaticity Transformation of the CIE Diagram , 1963 .

[22]  B H Crawford,et al.  INVITED ARTICLE: The colour rendering properties of illuminants: the application of psychophysical measurements to their evaluation , 1963 .