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A11y 101: 1.4.1 Use of Color

Color is important. Color allows us to discern whether our fruit is ripe. We use color to control traffic. We spend time in school teaching kids their colors. We ask them to “Identify the red one.” But not all of us see color the same way, and some can’t see it at all. We cannot rely on it to be the sole means of communication.

A little color theory

Light hits an object, and the object applies a filter. This filter absorbs or reflects bands of the light spectrum. The filter is influenced by the materials used to make the object. This could be a pigment, but blue pigment is very rare in nature. When you see blue in animals, it is usually due to the structure not blocking blue light.

The eyes are made up of cones that absorb light. Humans have 3 cones, red, blue, and green. How much light hits each cone type also helps determine the color. Imagine a brand new tennis ball in full light glowing neon yellow. What happens if we cut the light in half? Is it still neon yellow? What if there is just enough light to see the ball? What color is it then?

Or was the tennis ball really neon green? Color blindness is the result of damage to the cones or them not fully developing. There are brain and optical nerve injuries that can cause it as well. To put it short:

My navy blue is not the same as your navy blue.

Trying not to put the horse before Decartes, but our brains are amazing machines. It takes in a extreme volume of stimuli and builds the world around us. While we teach each other a standard that allows us to participate in a society. But when you view blue (or any color), you don’t just get blue light, you get color influence. The colors surrounding your object will change how the colors appear.

These two circles are the same color. But they don’t look like it due to the backgrounds.

Two grey circles of the same color against different backgrounds. One background is pink and the other is purple.

My wife has suffered several strokes and TBIs. We don’t see the same colors. It’s especially noticeable in the transition zones between colors. She asked me to grab something for her, but I couldn’t find it. She told me it was orange. Looking around I thought I found it, but it was red. She swears up and down it is orange. We’ve repeated this discussion with pinks, blues, and greens as well.

We each interpret colors differently. Therefore, it is vitally important that color is not the only way of communicating important information.

Like this article? Then please share. If you want to discuss it, find me on LinkedIn or BlueSky. If you liked my philosophical joke, leave a note and use the “polyphony.”

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