So white light is when your brain sees a roughly matched signal level on all three color channels. So white would be all of whatever color receptors we evolved for the planet. It’s more of a signal overload than a color.
We actually can’t tell the difference between the mix of primary colors and the actual color. Take Cyan at about 490nm. Looking at it triggers your red, blue, and green receptors in a spefic set of levels your brain reads as Cyan.
However your brain can’t tell the difference between a signal at 490nm and the right combination of 440, 540, and 580 nm. So for example a tv can only show 3 colors but your eyes and brain can’t tell the difference between that and all the natural colors.
We are the most sensitive to green because it’s the wavelength least used by photosynthesis and most plants reflect it. So we evolved to be extra sensitive to it. Camera sensors are usually 50% green, 25% red, 25% blue.
A small number of women have a mutation allowing them to see yellow. So some women can tell the side difference between true yellow and a primary color mix.
So white light is when your brain sees a roughly matched signal level on all three color channels. So white would be all of whatever color receptors we evolved for the planet. It’s more of a signal overload than a color.
We actually can’t tell the difference between the mix of primary colors and the actual color. Take Cyan at about 490nm. Looking at it triggers your red, blue, and green receptors in a spefic set of levels your brain reads as Cyan.
However your brain can’t tell the difference between a signal at 490nm and the right combination of 440, 540, and 580 nm. So for example a tv can only show 3 colors but your eyes and brain can’t tell the difference between that and all the natural colors.
We are the most sensitive to green because it’s the wavelength least used by photosynthesis and most plants reflect it. So we evolved to be extra sensitive to it. Camera sensors are usually 50% green, 25% red, 25% blue.
A small number of women have a mutation allowing them to see yellow. So some women can tell the side difference between true yellow and a primary color mix.
btw, this effect is called metamerism (wikipedia)