Approximately around 6% of the population has some form of color blindness.

All people see with their eyes and to see anything at all our eyes rely on our photoreceptors. There are two different types of them: rods and cones. Both of them are sitting on the retina at the back of your eye and pass information our irises collect on to our brain. The rods are sensitive to light while the cones pick up color.

Each eye has three cones in their photoreceptors that are carrying the three different photopigments – red, green and blue. The cones react differently on colored light sources. For each of this three types there exists a specific color absorption curve with peaks at different points in the color spectrum. Mixing together the information of those three different types of cones makes up our color vision.

When the cones capabilities to absorb and process color cones malfunctions it results in altered color vision, broadly known as Colorblidness.

The 3 types of colorblindness

There are three main types of colorblindness: Deutan, Protan and Tritan.

The Deuteran and Protan inefficiencies are the most common ones and can be split into 2 subconditions each:

• Deuteranomaly: malfunctioning green cone (common)
• Deuteranopia: missing green cone (rare)
• Protanomaly: malfunctioning red cone (rare)
• Protanopia: missing red cone (rare)

Blue-type colorblindness is also possible, but it is very, very rare.

One of twelve males are colorblind. Only an estimated 0.3% of the female population is colorblind.

There are many people who think the colorblind can’t see any color. But the term is misleading, more than 99% of all colorblind people can see color. People with the two most common types of colorblindness don’t really suffer a radical change in the way they see color.
However, they do have limited ability to distinguish between reds and greens (and any other color that has their missing color in it), especially in shades of a certain color. Something might look green, but in certain situations it could also look red or blue. Subtle tones, where the missing color is really low saturated might end up looking grey or even white. This can happen with soft beige tones, soft pink colors, and many many washed colors that look grey to people with Red or Green colorblindness.

The red and green cones lie quite close to each other in what colors they perceive (see the graphs above). They intersect at various points; when the green cones don’t work, the red ones still pick up some green – and the other way around.
The greens might not be as green as a non-colorblind person would perceive it, but it’s still within the category we would call green.

The following table lists some of the most problematic colors for each main type of colorblindness:

In conclusion, the colorblind people have a narrowed color perception. Green is still green and red stays red most of the time, but not as vibrant or bright as a non color blind would see it.

The majority of the contents of this article is taken from wearecolorblind.com. The information is used with permission from the lovely team over in Amsterdam.