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From: john@frog.UUCP
Newsgroups: sci.misc
Subject: Re: Color
Message-ID: <1961@frog.UUCP>
Date: Fri, 4-Dec-87 16:58:00 EST
Article-I.D.: frog.1961
Posted: Fri Dec  4 16:58:00 1987
Date-Received: Wed, 9-Dec-87 21:13:35 EST
References: <162300002@uiucdcsb>
Organization: Superfrog Heaven [ CRDS, Framingham MA ]
Lines: 23

In article <162300002@uiucdcsb>, kadie@uiucdcsb.cs.uiuc.edu writes:
> I've got two miscellaneous science questions. 
> 1) On TV's and computers screens, why is it RGB (red, green, blue)
> instead of RYB (red, yellow, blue) the primary colors?
Red, yellow, and blue are the primary *pigments*, which work by absorbing
the contrasting primary light colors.

> 2) Some light wave length produces the color green. A mixture of
> the wave lengths of blue and yellow also produces green.
> Even though these two greens are indistinguishable to our eyes, are there
> (could there be) instruments that distinguish them?

A prism.  Real green light in, green light out.  Apparent green light in,
blue and yellow lines out.

--
John Woods, Charles River Data Systems, Framingham MA, (617) 626-1101
...!decvax!frog!john, ...!mit-eddie!jfw, jfw@eddie.mit.edu

"Cutting the space budget really restores my faith in humanity.  It
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business of hate, debauchery, and self-annihilation."
		-- Johnny Hart