Although no one knows who invented the prism, Sir Isaac Newton was the one who discovered that the rainbows they produced were merely the components of white light that had been separated.
What is White Light?
Usually just called light or “visible light,” white light comes from the sun. It can also be produced by incandescent light bulbs, fires, or anything that gets hot enough to emit visible light.
How White Light becomes a Rainbow
When light shines through a prism it enters at an angle and exits at another angle. Different frequencies (color) of light are refracted at slightly different angles when they enter and exit the prism at an angle. Refraction is the change of direction that occurs when any type of wave goes into a different material at an angle.
Because the diffraction angle is different for different colors, the white light gets separated into different colors as it passes in and out of the prism.
What Colors come from a Prism
Although people can perceive around 10 million colors, prism colors are classified as one of the following seven:
How to get a Bigger Colors from a Prism
The further away the prism is from the target surface, the larger but also dimmer the colors will be. If you have a dark room and a bright sun, it will show up beautifully at a distant wall.
The closer to the prism the more brighter and bunched up the colors become. If you get too close to the prism then you will not be able to distinguish the colors anymore.
Color Lessons for Children
Catch the Rainbow.
Younger children love to chase the rainbow along the wall and around the room as you tilt the prism. They will try to catch the rainbow in their hands.
Children of all ages can make observations of the prism’s rainbow. Preschool children, like the 2- and 4-year-old pictured here can describe what they see. Ask if they hear, smell, or feel the rainbow.
For older children, ask if the colors are in separate bands or if they run together. Is each color equally wide, or are some wider than others?
Color what you see.
Have the prism shine onto a table or other solid surface, provide a variety of crayons and have them color what they see or color around it.
Test different light sources.
Try a strand of colored Christmas lights–what colors come out of the prism? What about that yellowish light in the lamp? Or a black light?
If using Sunlight
Keep in mind that the earth is rotating, so if you are using sunlight the color will move and you may have to readjust the prism for maximum color and shape.