Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!purdue!tut.cis.ohio-state.edu!ucbvax!hplabs!hpfcdc!hpfcdq!jlg
From: jlg@hpfcdq.HP.COM (Jeff Gerckens)
Newsgroups: comp.graphics
Subject: Re: Fequency (wavelength) to CIE XYZ
Message-ID: <390035@hpfcdq.HP.COM>
Date: 5 Jul 89 18:22:41 GMT
References: <609@becker.UUCP>
Organization: Hewlett-Packard - Fort Collins, CO
Lines: 32

> In article <8594@pyr.gatech.EDU> ccoprrm@pyr.gatech.edu.UUCP (ROBERT E. MINSK) writes:
> |
> |   Does anyone have a program or know of an algorithm to convert from
> |Frequency (or wavelength) to CIE XYZ coordinate space.  I am not looking
> |for CIE to RGB or for manipulations within the color space; this I 
> |already know how to do.
> 
> This is off the top of my head, so it will need some
> refinement...
> 
> Tables exist in several places which map the periphery
> of the CIE standard visibility gamut in 5-nanometer
> increments (or sometimes other resolutions), expressed
> in CIE coordinates.
> Given this polygon, you can interpolate the wavelength
> into its border so as to arrive at the fully saturated
> CIE coordinate value. Other saturations occur monotonically
> on a line from there to the current reference white point.
> The transformation from the (x,y,Y) coordinate system
> (if needed), to (X,Y,Z) is simple.

Tables can be found in :

   Color in Business, Science, and Industry by Deanne Judd,

and 

   Color Science: Concepts and Methods, Quantitative Data and
   Formulae by Wyszecki and Stiles

- Jeff Gerckens, Graphics Technology Division, Hewlett-Packard
  jlg%hpfcrg.fc.hp@hplabs.hp.com