Light Mixing> By itself, red light looks red, and blue light looks blue. Mix together all the <#5382,14><!rainbow> colors of light -- red, orange, yellow, green, blue and violet - and you get white-colored light.
But what if you just mix together two colors of light, like red and blue? Try it! Place a piece of red cellophane over a flashlight. Then place a piece of blue cellophane over another flashlight. Shine the two lights on a wall in a dark room so the red and blue spots overlap. Where the red and blue lights land together, you should see a new color ... <#5649,5125><!Magenta>!
What happened? Both red and blue light traveled to the same spot on the wall, bounced off, and back into your eye. When your eye combined the two, you saw a new color. Mixing colors of light so they add together in your eye is called additive color mixing.
Add green light and red light, and you get yellow light! Mix green light and blue light, and you get <#5650,5126><!cyan>-colored light (blue-green). It turns out that by mixing just three particular colors of light - red, green, and blue - you can make nearly all of the colors you can see, including white light. We call red, green, and blue light additive primary colors.
Don’t believe me? Use a wet finger to put a small drop of water on the middle of the computer screen in front of you. The drop works like a powerful magnifying <#5380,12><!lens>. You should see tiny dots or stripes of color in the drop. How many colors can you see? What are they? Try looking at different colors on the screen. (By the way, don’t forget to wipe off the screen when you are finished!)
Concerts and theater performances use colored lights all the time to set the mood of a scene, or to convince you it is sunset, or sunrise. The lighting person may mix together dozens of lights, each with their own color, to create just the perfect color for a scene.
