Wellenlaengen Color Measurement
CIE Lab Color Space
The most commonly used system in practical application, aside from the CIE color triangle, is the nearly perception-true L*, a*, b* system that was developed by Judd and Hunter and standardized in 1976.

In this system, the L* value indicates the position on the light-dark axis, the a* value indicates the position on the red/green axis, and the b* value indicates the position on the blue/yellow axis).

The L*, a*, b* coordinates are correlated directly to the standard color values, X, Y, and Z.

CIE_Lab
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