CIE 2-deg photopic luminosity curve (1924)

Data key

Columns

Energy

Linear

1. Wavelength (nm)
2. Photopic luminous efficiency, V(λ)
   

Logarithmic

1. Wavelength (nm)
2. log Photopic luminous efficiency, V(λ)

 

Quantal

Logarithmic

1. Wavelength (nm)
2. log Photopic luminous efficiency, V(λ)
   

Notes

From Wyszecki and Stiles (1982), Table I(3.3.1).

    The standard photopic luminosity function is based on a curious combination of luminosity data from several sources and obtained by several methods (Gibson & Tyndall, 1923; CIE, 1926). The uncertainty surrounding it is illustrated by the fact that the values from the different studies that were averaged to define it diverged by as much as a factor of ten in the violet (CIE, 1926; Le Grand, 1968). The function seriously underestimates sensitivity at short wavelengths.

References

CIE (1926). Commission Internationale de l'Eclairage Proceedings, 1924. Cambridge: Cambridge University Press.

Gibson, K. S., & Tyndall, E. P. T. (1923). Visibility of radiant energy. Scientific Papers of the Bureau of Standards, 19, 131-191.

Le Grand, Y. (1968). Light, colour and vision (2nd ed.). London: Chapman and Hall.

Wyszecki, G., & Stiles, W. S. (1982). Color Science: concepts and methods, quantitative data and formulae. (2nd ed.). New York: Wiley.