luminsivity: Luminous Efficiency Functions (photopic and scotopic)

In colorSpec: Color Calculations with Emphasis on Spectral Data

Luminous Efficiency Functions (photopic and scotopic)

Description

luminsivity.1nm

Four luminous efficiency functions, from 360 to 830 nm, at 1nm step

Format

A colorSpec object, with quantity 'energy->neural', and with 4 spectra:

photopic1924

The luminous efficiency function adopted by the CIE in 1924, and defining the standard photopic observer. It is only to be used when light levels are high enough that the sensitivity of the eye is mediated by cones, and not rods. It is the same as the y-bar function in xyz1931.1nm. It is used to define the candela in the International System (SI) and is the only one of these functions to appear in the SI. It was downloaded from http://www.cvrl.org/database/data/lum/vl1924e_1.csv where it is defined from 360 to 830 nm.

scotopic1951

The luminous efficiency function adopted by the CIE in 1951, and defining the standard scotopic observer. It is only to be used when light levels are low enough to exclude the activation of cones. It has no effective role in colorimetry. It was downloaded from http://www.cvrl.org/database/data/lum/scvle_1.csv where it is defined from 380 to 780 nm. It has been padded with 0s to 360 to 830 nm.

photopic1978

The luminous efficiency function for photopic vision, with adjustments in the blue region by Judd (1951) and Vos (1978). It was published by the CIE in 1988. It was downloaded from http://www.cvrl.org/database/data/lum/vme_1.csv where it is defined from 380 to 780 nm. It has been padded with 0s to 360 to 830 nm.

photopic2008

The CIE (2008) physiologically-relevant luminous efficiency function for photopic vision, by Stockman, Jagle, Pirzer, & Sharpe. It was downloaded from http://www.cvrl.org/database/data/lum/linCIE2008v2e_1.csv where it is defined from 390 to 830 nm. It has been padded with 0s to 360 to 830 nm.

Note

Luminsivity is a self-coined portmanteau word: luminsivity = luminous * responsivity. The word is unrelated to emissivity. The term luminous responsivity is not common, but appears on page 15 of Grum. The term luminous efficiency function is standard, but too long. The term luminosity function is common, but luminosity is ambiguous and also appears in astronomy and scattering theory.
The object luminsivity.1nm is used by the function photometric().

Source

Colour & Vision Research Laboratory. Institute of Opthalmology. University College London. UK. http://www.cvrl.org/

References

Grum, Franc and Richard J. Becherer. Radiometry. Optical Radiation Measurements, Volume 1. Academic Press. 1979.

Stockman, A., Jagle, H., Pirzer, M., & Sharpe, L. T. (2008). The dependence of luminous efficiency on chromatic adaptation. Journal of Vision, 8, 16:1, 1-26.

See Also

xyz1931.1nm, photometric

Examples

summary(luminsivity.1nm)
product( D65.1nm, luminsivity.1nm, wave='auto' )

colorSpec documentation built on May 29, 2024, 6 a.m.