Is color one wave of light or many waves together?

[seriously disabled]

When we see the color green (green is 490 nm - 560 nm on the electromagnetic spectrum), is it many electromagnetic waves or only one wave?

[swansont]

Do you mean one wavelength, or one oscillation?

 

Assuming you mean wavelength, it depends on the circumstances. Color is not only dependent on the wavelength, but how your eyes and brain interpret the signal they get. Green can be green because it's one wavelength, but it can also be green because it's multiple wavelengths, e.g. adding red yellow and blue light.

Edited September 3, 2009 by swansont

[insane_alien]

red and blue gives you magenta swansont. thought you were one of those physics experts.

[McCrunchy]

http://mysite.verizon.net/vzeoacw1/coloradd.html

 

McCrunchy

[insane_alien]

that site seems to require an application to run. firefox reports it as unknown

[swansont]

red and blue gives you magenta swansont. thought you were one of those physics experts.

 

Color addition is biology, not physics. Still: D'oh! Yellow and blue.

[seriously disabled]

Assuming you mean wavelength, it depends on the circumstances. Color is not only dependent on the wavelength, but how your eyes and brain interpret the signal they get. Green can be green because it's one wavelength, but it can also be green because it's multiple wavelengths, e.g. adding red yellow and blue light.

 

No. What I meant is whether the color green is only one electromagnetic wave or many electromagnetic waves together. If it's many waves, does the color get brighter?

[Klaynos]

No. What I meant is whether the color green is only one electromagnetic wave or many electromagnetic waves together. If it's many waves, does the color get brighter?

 

Light is quantised into packets, when we see the colour green photons (many of them) are hitting the light receptors in our eyes in such a pattern as our brain thinks green.

 

You can build detectors to detect a single green photon though.

[seriously disabled]

But that wasn't my question.

 

My question was whether the color green is many electromagnetic waves of a certain wavelength or only one electromagnetic wave of this wavelength?

[swansont]

"Many waves" isn't a well-defined term. There is a minimum amount of energy you can have, and that can be green light. You can have many of these, which we call photons, and have brighter green light. If you look at the wave aspect, the wave will have a higher amplitude.

[seriously disabled]

"Many waves" isn't a well-defined term. There is a minimum amount of energy you can have, and that can be green light. You can have many of these, which we call photons, and have brighter green light. If you look at the wave aspect, the wave will have a higher amplitude.

 

No what I meant is what if there are 3 or 4 electromagnetic waves of the color green entering the eye simultaneously?

 

If this is the case, what will we see then?

Edited September 3, 2009 by Uri

[MDJH]

I'm guessing this topic is about the confusing explanations of light. I recall using the program Paintbrush (sort of like an older version of MS Paint) as a little kid and playing around with the RGB thing to see different combinations of colours, later reading the section on colour of dad's physics book, and got the impression that for light, colours other than red, green, and blue were typically the products of those two... including white itself. Of course, that semeed to contradicted what I learned in art class, but that was supposedly about pigments anyway so it wasn't too confusing.

 

But when learning about how light is made of "photons" how higher energy photons have shorter wavelengths, and how it's more of a continuous thing than a definite thing, then reading elsewhere about how prisms separate white light into the colours of the rainbow, but don't separate one colour into its "constituents" it just seems right contradictory. What's the real story?

[swansont]

No what I meant is what if there are 3 or 4 electromagnetic waves of the color green entering the eye simultaneously?

 

If this is the case, what will we see then?

 

More photons will look brighter.

[MDJH]

More photons will look brighter.

But what if it's a mix of equal parts blue photons, green photons, and yellow photons? Will it still look green? If so, would a prism separate those colours?

[seriously disabled]

But what if it's a mix of equal parts blue photons, green photons, and yellow photons? Will it still look green? If so, would a prism separate those colours?

 

No because blue, green and yellow are the fundamental colors of light. They are called primary colors. Light with a wavelength of 570–580 nm is yellow, light with a wavelength of roughly 440–490 nm is blue and light with a wavelength of roughly 520–570 nanometres is green.

 

White light is the effect of combining the visible colors of light in equal proportions.

[insane_alien]

actually whit would need to be composed of red green and blue.

 

this evidenced by the screen you're looking at right now. one that used yellow instead of red would not be able to display red or even orange. magenta would also be out of the question.

 

this is due to the fact that humans have only three different types of colour detecting cells(okay, some people have a mutation which gives them a 4th that does yellow but they're few and far between) one for red one for green and one for blue. this is why you can make the whole visible spectrum(more or less) with only three colours. otherwise we'd need some sort of variable wavelength emitter for tv screens

[swansont]

But what if it's a mix of equal parts blue photons, green photons, and yellow photons? Will it still look green? If so, would a prism separate those colours?

 

Whatever color you got from the mixture, the individual wavelengths would separate when sent through a prism.

[MDJH]

actually whit would need to be composed of red green and blue.

 

this evidenced by the screen you're looking at right now. one that used yellow instead of red would not be able to display red or even orange. magenta would also be out of the question.

 

this is due to the fact that humans have only three different types of colour detecting cells(okay, some people have a mutation which gives them a 4th that does yellow but they're few and far between) one for red one for green and one for blue. this is why you can make the whole visible spectrum(more or less) with only three colours. otherwise we'd need some sort of variable wavelength emitter for tv screens

... any proof of this? Don't get me wrong, you seem to know what you're talking about, just want a source to check on since people on the Internet don't necessarily mean what they say.

 

In any case, if we have cells for red, cells for green, and cells for blue, then how would we tell the difference between photons of green light that are closer to red than to blue and photons of green light that are closer to blue than to red? (Or can we?)

[iNow]

MDJH - You can google the "trichromatic theory of vision" to learn more.

 

Here's a quick wiki:

http://en.wikipedia.org/wiki/Trichromacy

 

It has to do with the cone cell photoreceptors in our eyes:

http://en.wikipedia.org/wiki/Cone_cell

http://en.wikipedia.org/wiki/Color_vision

[insane_alien]

well, iNow has posted links for me. if you don't trust wikipedia too much then look at the references on those pages.

[MDJH]

well, iNow has posted links for me. if you don't trust wikipedia too much then look at the references on those pages.

I'm actually not inclined to look through the articles or their sources right now... but I'm convinced that I believe you. I'll probably look into them later.

[Klaynos]

The detector cells don't detect a single frequency, but detect a range at different efficiencies, these ranges overlap, our brain interoperates the signals from each of the type of cell to give a colour.