what colour is 'pure' light?

Answer 1

As others have observed the word "pure" is difficult to interpret in relation to light. What would impure light be? In as much as light is light and nothing else then all light is pure light.

What is more interesting is to ask what light is, and what colour is.

In the physical universe we have electromagnetic radiation. This would exist whether eyes existed or not. Electromagnetic radiation has different properties according to its frequency. Radio waves, microwaves, ultra-violet, and infra-red radiation are all electromagnetic radiation at different frequencies, and one particular frequency band we call "light". The only thing special about that frequency band is that on entering the eye, it affects the retinal chemistry, and sets up nerve impulses in the Optic nerve, which stimulate the brain to manufacture the experience we call "Vision".

Colours are visual experiences generated by the brain in response to specific frequencies within the "light" frequency band. A "pure" frequency of light will generate a specific colour: a combination of frequencies will combine to create a brighter experience of the combined colours, and when all the "colour sensors" are switched on together we have an experience of white or golden light.

Light and colour are properties of consciousness, and not of the physical universe. Understood in this way, "pure light", is like the bulb in a video projector. If we show a video of the sunrise on a projector, the "pure light" is the projector bulb, and to get the scene of the sunrise, that pure light has to be passed through an LCD screen to filter it in different ways. Some parts are filtered to be black, and some red, and where the sun appears, is perhaps the "pure light" of the bulb not filtered at all. The brightest light that can appear on the screen is the "pure light" of the bulb.

Similarly in our own consciousness the "pure light" is the white or golden light, which is the maximum visual experience, like a thousand suns all shining together, but this is filtered by the mechanism of the eye, to be the ordinary everyday vision of the world.

Answer 2

Pure - or white - light is every colour. Put a prism in a shaft of sunlight and you will see the light split into all the colours of the spectrum.

Red
Orange
Yellow
Green
Blue
Indigo
Violet

Or ... Richard Of York Gave Battle In Vain

A natural evidence of a prism in action is a rainbow, this occurs when the light is split as the sunlight catches the last of the raindrops. I think it's a very reassuring sight, it means the rain is over and the sky is clearing.

Answer 3

What colour is colour?

The rainbow gives you an idea of all the colours of visible light. Each wavelength of light will give you a different colour.

You can have a pure red if you like or a pure green.

White light is a mixture of all the colours and is not pure.

Answer 4

when you write 'pure' in quotes it begs a definition.

definition 1: pure means white -then one can demonstrate that white light can be separated into other colours with a prism.

definition 2: pure means monochromatic -i.e. a colour that will not be separated by a prism into components

definition 3: light means in the visible spectrum; then in combination with definition 2 pure light means any monochromatic colour.

Answer 5

There is no such thing as "pure" light per se. Light is visible in several colors due to varying wavelengths and frequencies. Red has the longest wavelength and least frequency while violet has the shortest and highest. But not one is any more a form of light than the other. White has come up a few times because it is a result of good reflection. Objects that are white mean they are good reflectors (as oppose to absorbers and emitters) and thus are able to relfect radiant energy - which obviously includes visible light. Light colored objects thus reflect more and white is when all is reflected. As oppose to black which means all radiant energy, inc visible light, is absorbed. Darker colored objects mean they're better absorbers and emitters as oppose to reflectors.

Answer 6

The term "pure" is ill-defined. By pure I would mean monochromatic. So white light is a very impure mixture. Pure light could come in any color of the rainbow.

Answer 7

did you never do the experiment with the spinning disk with a coloured segment for each colour of the rainbow. When you spin the fast they make white. Pure light is white.
Hope this helps. x

Answer 8

Actually, if you use a prism the pure light is a spectrum of many colours.

Answer 9

pure light can be any color. If you have some wavelengths taken out, you get different colors. Light starts out white, because thats what all the wavelengths make put together. But when some wavelengths are taken out, or absorbed by objects, thats why you see different colors

Answer 10

White light is a combination of all colors, that is the reason when it rains you can see a rainbrown, because the whithe light of the sun is divided into its components when it passes through a prism. (the water)