Why Do Some People See Green in the Red Light?

Some people see green when they look at red light because their eyes work a little differently.

Imagine you have two special glasses: one that turns red things into green and another that doesn’t. Most people wear the second kind of glasses, but some wear the first one. That’s why they see green in the red light, it's like looking at a red apple through a green filter, and suddenly it looks green to them.

Your eyes have little helpers called cones that help you see colors. Most people have cones that are good at seeing red, green, and blue. But some people have a special kind of cone, or maybe just one more than usual, that helps them mix the colors differently. This is like having an extra color in your paint box. When they look at red, their brain mixes it up and sees green instead.

It's like when you wear sunglasses on a sunny day, everything looks darker. Some people see green in red because their eyes are like special sunglasses for colors, and that makes red look green to them!