How can I know how good is a color display? This is when the CIE xy chromaticity coordinates come through.
So first, how does the eye perceive color? We know that our color primaries (red, green, blue) can form a color and a mixture of this is a color pixel in a color display like a TV. The CIE color matching functions are like the spectral sensitivity of the eye to the color primaries. It is because they are derived from a human observer.
To do this I need to plot an CIE xy chromaticity diagram.
So I used these equations:
where K is a normalizing function, P is the power distribution of some object Q, and X,Y,Z are the color matching functions that I downloaded from the web. The power distribution that I used is the dirac delta function for every monochromatic wavelength from 380 nm to 780 nm with increments of 5nm. This is so that I can form the bounds of the CIE xy chromaticity diagram. [1]
Now you can get the CIE xy chromaticity coordinates using these equations[1]:
and
And I plottted the CIE xy chromaticity diagram using equations 1-5.
Figure 1. Computed CIE xy tongue. |
Figure 2. Reference CIE xy tongue from Wikipedia.org |
References:
[1]J.Soriano, AP 186 manual - CIE xy Chromaticity Diagrams 2010, 2014.
[2]CIE 1931 color space, http://en.wikipedia.org/wiki/CIE_1931_color_space
For CIE xy tongue comparison map:
[3] http://upload.wikimedia.org/wikipedia/commons/thumb/3/3b/CIE1931xy_blank.svg/450px-CIE1931xy_blank.svg.png
For colloidal quantum dots:
[4] http://www.nano-reviews.net/index.php/nano/article/view/5202/5767#F0003
For the CIE's color matching functions:
[5] http://www.cvrl.org/cmfs.htm
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