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Why did CIE choose 700nm, 546.1nm and 435.8nm as bases in the first place?


I found it cool that we could take three specific frequencies and reconstruct a color that is totally different than the original three colors when perceived by the eye.


Can someone explain the concept of a color needing "negative red" to match?


@ecohen2 We try to find the combination of Red, Green, and Blue that creates the same perceived color as the color we are trying to match (let's call this C). Sometimes regardless of the combinations of colors we try, we cannot match C exactly. However, sometimes we can in fact match C if we shine one of the Red, Green or Blue lasers on C--in this case, C + some amount of red = some amount of green + some amount of blue. In this scenario, since red has been added to the color we are trying to match, not in the creation of our own color, we consider it "negative red" since we have added to the other side.


@cat Laser can only emit single-wavelength light at some selected frequencies, not any arbitrary frequency on a continuous spectrum. It is related to materials.