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CIE 1976 uniform-chromaticity-scale diagram

CIE 1976 UCS diagram

uniform chromaticity scale diagram produced by plotting in rectangular coordinates v′ against u′, quantities defined by the equations:
u′ = 4 X / (X + 15Y + 3Z) = 4x / (−2x + 12y + 3)
v′ = 9 Y / (X + 15Y + 3Z) = 9y / (−2x +12y + 3)
where X, Y, Z are the tristimulus values in the CIE 1931 or 1964 standard colorimetric systems, and x, y are the corresponding chromaticity coordinates of the colour stimulus considered

Note 1 to entry: The CIE 1976 uniform-chromaticity-scale diagram is a modification of, and supersedes, the CIE 1960 uniform-chromaticity-scale diagram in which v was plotted against u in rectangular coordinates. The relationships between the two pairs of coordinates are: u′ = u; v′ = 1,5 v.

Note 2 to entry: This entry was numbered 845-03-53 in IEC 60050-845:1987.

Note 3 to entry: This entry was numbered 17-162 and 17-161 in CIE S 017:2011.

Publication date: 2020-12
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