How We See Color

There are three types of color receptors in your eye: red, green and blue. But how do we see the kaleidoscope of other colors that make up our world? Colm Kelleher explains how humans can see everything from auburn to aquamarine.

Think About It

1. Discuss the concept of “physical color” and how it does not tell the whole story.
2. Kelleher states that “because light is a wave, two different frequencies shouldn’t interact with each other at all.” Expound on why that should not happen and what is occurring that is allowing it to happen.
3. Explain the function of the Retina in seeing color.
4. There is only one of these light-detecting cells; what is it called? What does it allow us to see?
5. Describe how your eye is able to see yellow. Explain in detail the process that occurs.
6. Compare and contrast what happens in your eye and brain when you see blue verses purple.
7. Explain what prevents us from seeing colors in the dark?
8. Identify the two signals your brain receives in the dark?
9. Explore the benefits of only having three color-detecting cells. How does that impact the real world?
10. Hypothesize what happens when someone is color-blind. How do you think their ability to see colors is impacted?

Do It

• Pay attention to how many things in your daily life are not just red, green or blue.
• Experiment to see how much light you need to have in order to see color.
• Interview someone who knows they are color blind and explore the differences each of you see in an image.
• Learn more about color with the Mensa for Kids Introduction to Color lesson plan.

Read About It

• Watch Colm Kelleher’s Ted Talk on the physics behind color.
• Listen to Colm Kelleher’s Ted Talk that explores the question of whether light is exclusively a wave or just a particle.

Watch It

• Learn more about how we see color.
• Learn about hue, value, and saturation — the three main integral parts of color.
• Learn more about the science of color.
• Read about the different properties of color.