Assume that people with normal color vision perceive all colors on a display as the cubic region of a color space like opponent color space, shown in the following figure (a).
Then people with color blindness perceive the same color as the region near the two-dimensional plane, shown in the figure (b) or (c).
The following figure shows how Visolve Red-Green transform transforms the colors in the color space.
(It is a cross-sectional view of the color space viewed from the direction of the yellow-blue axis.)
In colors of the same brightness, redder colors are transformed to brighter, and greener colors are transformed to darker.
Protan and deutan observers can perceive luminance-element and yellow-blue-element from original colors.
And they see changes by Red-Green transform which reflects red-green-element on luminance-element.
As a result, they could obtain three-dimensional information.
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| Location of original colors | Location of transformed colors |
Blue-Yellow transform transforms colors in the same way as this with respect to the luminance and yellow-blue axes.