spectral luminous efficiency

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efficiency, spectral luminous (of a monochromatic radiation of wavelength λ)

Ratio of the radiant flux at wavelength λm to that at wavelength λ such that both radiations produce equally intense luminous sensations under specified photometric conditions and λm is chosen so that the maximum value of this ratio is equal to one. Symbols: V(λ) for photopic vision. V′(λ) for scotopic vision (Fig. E1). Note: unless otherwise indicated, the values used for the spectral luminous efficiency in photopic vision are the values agreed internationally in 1931 by the CIE and adopted in 1933 by the International Committee on Weights and Measures. For scotopic vision the CIE in 1951 provisionally adopted new values for young observers (CIE). Syn. luminosity curve.
Fig. E1 Relative luminous efficiency curves for photopic V λ and scotopic V′ λ levels of adaptation for an equi-energy spectrum. These data represent the sensitivity (i.eenlarge picture
Fig. E1 Relative luminous efficiency curves for photopic Vλ and scotopic V′λ levels of adaptation for an equi-energy spectrum. These data represent the sensitivity (i.e

Table E1 Photopic and scotopic relative luminous efficiency factors. The data are based on an average from a large number of individuals agreed by the CIE in 1931 for the photopic factor Vλ and in 1951 for the scotopic factor V′λ
wavelength
(in nm)
VλVλ
3800.000 00.000 589
4000.000 40.009 292
4200.004 00.096 61
4400.023 00.328 1
4600.060 00.567 2
4800.139 00.793 0
5000.323 00.981 8
507-1.000 0
5200.710 00.935 2
5400.954 00.649 7
5551.000 0-
5800.870 00.121 2
6000.631 00.033 15
6200.381 00.007 374
6400.175 00.001 497
6600.061 00.000 312 9
6800.017 00.000 071 55
7000.004 10.000 017 80
7200.001 050.000 004 78
7400.000 250.000 001 379
7600.000 060.000 000 425
7800.000 000.000 000 139