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I'm sorry some of you may mark this question as duplicate, but even though I searched over about this I couldn't get satisfacory answer. Also I think this question is more related to biology, but I dont think I would get a satisfactory answer on biology forum.
I have had much intesest in color perception. I learned that color is just illusion of human brain to interpret electromagnetic spectrum. But though I'm physics grad student, I never questioned myself why there is no white color in visible ray spectrum. I realized that today. Sure thing, I learned when I was young that white color is
what we see when we see an object that reflect all the light.
But what do we mean by 'all the light' here? every illuminant has different spectral power distribution so even if an object reflects them all what we see would depends on illuminant. And what does it means that it reflects every light? surely not all the electromagnetic spectrum. Only visible rays? reflects 400nm but not 390nm? I'm not sure about that.
Equal composition of RGB, three primary colors.
If you see the CIE color space picture with sRGB gamut on it, you would question whether we can call these colors 'primary'.
Yes we humans have three types of cones, but they don't correspond exactly to each color of RGB.
I thought white should be a extreme on certain measure (like lightness in 'conventional' term) but Im not sure which is corresponding scientific term. Or isnt white such a special color? just some 'appropriate' mixture of colors like RGB?
I read some articles about this on Wikipedia but I'm not sure I understood them because they use many technical terms in color science.