Colo(u)r sense

[Spencer Thiel]

At 10:13 PM +0100 8/20/99, JL wrote:

>The eye/brain perceives this particular combination of wavelengths as a
>single purplish colour.  Of course, this resultant colour 'mauve' does have
>an equivalent single-wavelength which exists in the normal visible spectrum.

It does?  As far as I can tell, there is no mauve (or any other 
colors that require combinations, such as white) on the 
electromagnetic spectrum--the closest is violet which is a very dark 
(as perceived by us) frequency range.  If you want to make a 'light 
purple' you have to combine colors.  Eyes perceive the color (crudely 
put) by summing the product of intensity and frequency of the 
incoming light.  If you mix red and blue, you get purple.  Just 
because a color exists, does not mean it is monospectral.  What this 
does mean is that you can have an amazingly complex combinations of 
light that will produce the same colors, as long as sum(I*F) is the 
same.


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