File talk:CIE illuminant F4 and a blackbody of 2938K.svg

Source code

L=380:5:780;
FL4=[0.57 0.7 0.87 0.98 2.01 13.75 1.95 1.59 1.76 1.93 2.1 30.28 8.03 2.55 2.7 2.82 2.91 2.99 3.04 3.08 3.09 3.09 3.14 3.06 3 2.98 3.01 3.14 3.41 3.9 4.69 5.81 7.32 22.59 15.11 13.88 16.33 18.68 20.64 24.28 26.26 23.28 22.94 22.14 20.91 19.43 17.74 16 14.42 12.56 10.93 9.52 8.18 7.01 6 5.11 4.36 3.69 3.13 2.64 2.24 1.91 1.7 1.39 1.18 1.03 0.88 0.74 0.64 0.54 0.49 0.46 0.42 0.37 0.37 0.33 0.35 0.36 0.31 0.26 0.19];
stairs(L,FL4);
hold;

l=380:780;
c2=1.4387752e+7;
bb_spd=5e+18*l.^(-5)./(exp(c2./(2937.8.*l))-1);
plot(l,bb_spd);
axis([380 780 0 35]);