File talk:CIE illuminants A,B,C.svg

Source code

l=380:5:780;
spda=100*(560./l).^5*(exp(1.435e7/(2848*560))-1)./(exp(1.435e7./(2848*l))-1);
spdb=[
22.4
26.85
31.3
36.18
41.3
46.62
52.1
57.7
63.2
68.37
73.1
77.31
80.8
83.44
85.4
86.88
88.3
90.08
92
93.75
95.2
96.23
96.5
95.71
94.2
92.37
90.7
89.65
89.5
90.43
92.2
94.46
96.9
99.16
101
102.2
102.8
102.92
102.6
101.9
101
100.07
99.2
98.44
98
98.08
98.5
99.06
99.7
100.36
101
101.56
102.2
103.05
103.9
104.59
105
105.08
104.9
104.55
103.9
102.84
101.6
100.38
99.1
97.7
96.2
94.6
92.9
91.1
89.4
88
86.9
85.9
85.2
84.8
84.7
84.9
85.4
86.1
87];
spdc=[
33
39.92
47.4
55.17
63.3
71.81
80.6
89.53
98.1
105.8
112.4
117.75
121.5
123.45
124
123.6
123.1
123.3
123.8
124.09
123.9
122.92
120.7
116.9
112.1
106.98
102.3
98.81
96.9
96.78
98
99.94
102.1
103.95
105.2
105.67
105.3
104.11
102.3
100.15
97.8
95.43
93.2
91.22
89.7
88.83
88.4
88.19
88.1
88.06
88
87.86
87.8
87.99
88.2
88.2
87.9
87.22
86.3
85.3
84
82.21
80.2
78.24
76.3
74.36
72.4
70.4
68.3
66.3
64.4
62.8
61.5
60.2
59.2
58.5
58.1
58
58.2
58.5
59.1];
plot(l,spda,'r',l,spdb,'g',l,spdc,'b');
axis([380 780 0 250])

Reference

• T. Smith and J. Guild (1931-2). "The C.I.E. colorimetric standards and their use". Transactions of the Optical Society 33 (3): 102. DOI:10.1088/1475-4878/33/3/301. "Table V. Energy distribution of the three standard illuminants A, B, C for colorimetry"