
386 OPTICS FOR ENGINEERS
x
y
0 0.2 0.4 0.6 0.8 1
0
0.2
0.4
0.6
0.8
1
2000 K
3000 K
3500 K
λ = 457.9 nm
λ = 530.9 nm
λ = 647.1 nm
RGB
Figure 12.12 (See color insert.) CIE (1931) chromaticity diagram. The coordinates x and
y are the chromaticity coordinates. The horseshoe-shaped boundary shows all the monochromatic
colors. The region inside this curve is the gamut of human vision. Three lasers define a color
space indicated by the black dashed triangle, and three fluorophores that might be used on a
television monitor define the color space in the white triangle. The white curve shows the locus
of blackbody radiation. The specific colors of three blackbody objects at