What wavelength is white?

[Phredy1]

Ok, the human eye can see between roughly 400nm and 700nm. We can see violet, blue, green, yellow and red and combinations of those. If we mix red, green and blue laser light we get white. I can see white but I can't see where white light would be in the color spectrum.

Does white light have a wavelength?

[swamidog]

white (light) is not a color. it is a combination of colors.

Ok, the human eye can see between roughly 400nm and 700nm. We can see violet, blue, green, yellow and red and combinations of those. If we mix red, green and blue laser light we get white. I can see white but I can't see where white light would be in the color spectrum.

Does white light have a wavelength?

[Phredy1]

white (light) is not a color. it is a combination of colors.

I understand it is a combination of all the colors. If I combine red and green I get yellow. Yellow has a wavelength. Blue and red combined makes purple. Purple has a wavelength. Why does red + blue + green = no wavelength?

Makes no sense to me....

[allthatwhichis]

Actually, red and blue make magenta; which does not have a wavelength. Red and green can make yellow, but yellow is also yellow by itself.

White light is the whole visible spectrum together; a sum of all the wavelengths between 400 to 700nm.

The universe was created to be experienced, not make sense...

[mikkojay]

You have to remember too that much/all? color mixing is happening in your brain, in that what your mind interprets as different color mixes is just the sum of what pure color inputs it has been given. The colors not might be "mixed" until they are speeding thru your optic nerves. Fun to think about..
-Mike

[Doc]

Just remember that the human eye is an RGB device; one perceives colour by summing of a relative levels of red green and blue even for a prime intermediate colour like true yellow.

The cones have an overlap in their response, so monochromatic yellow will trigger your red and green cones.

[kitatit]

Hi Gene,

I'm no guru on the subject but maybe a good way to visualize how it works is to compare it to a hearing test like you probably have to do for your job from time to time. You know how the little beeps start out low and each beep is higher than the next until you can't hear it anymore?

Each beep is a sine wave which is just one frequency like how most lasers only have one colour.

If you played all the tones at once it would sound kind of like white noise which is like white light.

Do a search on sine waves and what they look like when you mix different frequencies together. That might help.

Kit

[Eidetic]

What wavelength is brown? Muave? Beige? Pink? Get the point? You're mixing words that describe colors with words that describe radiation. The fact that a few are common to both worlds doesn't mean that all are.

[Phredy1]

Shit...I apologize. I knew better than to post something after that last Budweiser.

The answer is clear today. Combining red and green does not change the wavelengths. There is still only 532nm and 640nm wavelengths. It just appears yellow to the eye. Much the same as pixels on a tv screen.

WTF was I thinking? LOL

[mikkojay]

No need to apologize man! It's a cool concept that not many people think about and 99.999% of people just take for granted. If I tried to strike up this topic with most of my friends or family, they'd probably try to organize some kind of intervention..., but I think it's great
-Mike