Xref: utzoo sci.electronics:3906 rec.audio:8455 Path: utzoo!utgpu!attcan!uunet!pyrdc!pyrnj!rutgers!mcnc!unccvax!dya From: dya@unccvax.UUCP (York David Anthony @ WKTD, Wilmington, NC) Newsgroups: sci.electronics,rec.audio Subject: Re: Looking for Blue LEDs Keywords: blue blue blue, not yellow or red or green Message-ID: <1128@unccvax.UUCP> Date: 23 Sep 88 13:28:16 GMT References: <1138@nmtsun.nmt.edu> <862@ritcv.UUCP> <255@rna.UUCP> <4422@lynx.UUCP> <871@ritcv.UUCP> Organization: Univ. of NC at Charlotte, Charlotte, NC Lines: 18 In article <871@ritcv.UUCP>, cep4478@ritcv.UUCP (Christopher E. Piggott) writes: > Question: why are R.G.B. monitors Red, GREEN, blue, when GREEN is not one of > the primary colors (being a combination of blue and yellow)? Why shouldn't > it be red, YELLOW, blue? Actually, you are thinking about pigmented primary colour systems, not optical additive primary colour systems. The RGB primaries represent the maximum span (and define a "triangle" on the CIE colour chart, a 2-d representation of colour space) of reproducible colours. Colours outside the "span" cannot be reproduced. Check out any decent book on physical psychology, Cornsweet's classic text "Visual Perception", or the half-zillion books published on this subject in the 50's w.r.t. colour TV. York David Anthony DataSpan, Inc