Impossible colors or forbidden colors are hues that cannot be perceived by ordinary viewing conditions from light that is a combination of various intensities of the various frequencies of visible light. Examples of impossible colors are bluish-yellow and reddish-green. This does not mean the muddy brown color created when mixing red and green pigments (such as paints), or the green color from mixing yellow and blue pigments, but rather colors that appear to be similar to, for example, both red and green, or both yellow and blue. Other colors never experienced by ordinary viewing, but perceivable under special artificial laboratory conditions, would also be termed impossible colors.
We all know that it is impossible to imagine new color...But why is that so??
Recently a person who was blind from birth was treated and got his vision, and when he was able to see, doctors asked him to draw what it looked like or what he felt when he was blind. But for him the vision he got after being blind for many years was like a torture that he committed suicide.
There is a theory which stated in a simple way would mean that what looks like green for me would like red, blue or even white for some other person. This may go even the other way round. It is impossible to define a color. Its all about their own perception.
There are also evidences that can prove have seemed to prove the ability to see impossible color. The experiment During 1983, by Hewitt D. Crane and Thomas P. Piantanida is one such experiment.
They performed tests using a device that had a field of a vertical red stripe adjacent to a vertical green stripe (or in some cases, yellow–blue). In contrast to apparatus used for simpler tests, the device had the ability to track involuntary eye movement and to adjust mirrors so that the image would appear to be completely stable. The boundary of the red–green stripes was stabilised on the retina of one eye while the other eye was patched and the field outside the stripes was blanked with occluders. This allowed for a mixing of the two colors in the brain, producing neither green for a yellow–blue test, nor brown for a red–green test, but new colors entirely. Some of the volunteers for the experiment even reported that afterwards, they could still imagine the new colors for a period of time.
Other researchers dispute the existence of colors forbidden by opponency theory and claim they are, in reality, intermediate colors. See also
binocular rivalry.
In conclusion, its all about our own perception.
Source : http://en.wikipedia.org/wiki/Impossible_colors
