The Color Science

The Commission Internationale de l’ Eclairage (CIE) Photometry and Chrometry Knowledges

1. CIE 1931 color space

CIE XYZ color space was derived from experiments done in late 1920s by W. David Wright and John Guild. Their results were combined into the specification of the CIE RGB color space, from which the CIE XYZ color space was derived.

Tristimulus values, which in principal, are the three parameters describe a color sensation that a human eye being sensitive with (short-S, medium-M, and long-L wavelengths), are denoted as X, Y, and Z, respectively in the CIE 1931 color space. They are roughly represents the derived parameters of the Red, Green, and Blue colors, respectively.

2. CIE 1931 Standard Observer, Chrometry formula

3. CIE 1931 xy chromaticity diagram & xyY color space (Chromaticity Coordinates)

4. CIE 1976 (also known as CIELUV) color space

CIE 1976, or CIELUV, is an Adam’s chromatic valence color space that a simple-to-compute transformation of CIE 1931, but which attempted perceptual uniformity.

5. Standard illuminator

Illuminator
CIE 1931
CIE 1976
A, 2856K
x = 0.4476
u’ = 0.2560
y = 0.4075
v’ = 0.5243
B, 4874K
x = 0.3485
u’ = 0.2137
y = 0.3517
v’ = 0.4852
C, 6774K
x = 0.3101
u’ = 0.2009
y = 0.3163
v’ = 0.4610
D, 6504K
x = 0.3127
u’ = 0.1978
y = 0.3291
v’ = 0.4684
E, 5448K
x = 0.3333
u’ = 0.2105
y = 0.3333
v’ = 0.4737

6. Hg spectrum line

404.66 nm

435.88 nm

546.07 nm

576.96 nm

579.00 nm