C.I.E. Chromaticity Diagram
Sencore as a gesture of
gratitude for allowing the use of their industry standard C.I.E. Chromaticity Chart.
Here is a very detailed dissertation on the subject of
chromaticity, along with
software for generating multiple version of the chart.
Chromaticity is commonly defined as the quality of
color characterized by its dominant or complementary wavelength and purity taken together. This chromaticity chart
human tristimulus color space according to:
x = X/(X + Y + Z),
y = Y/(X + Y + Z).
Colors along the periphery of the "horseshoe" plot (spectral locus) are pure, monochromatic, saturated colors.
Less saturated colors approach the center becomes (i.e. it becomes whitish or grayish). The straight line across
the bottom is called the "non-spectral line of purples."