Right angle prisms are great for examining the principle of total internal reflection.
If the light comes through the light crystal heading out to a surface in air at a large enough angle, the increase in speed as it tries to go back out into air makes it change direction back into the light crystal. When this happens, we have "total internal reflection" of the light.
Click to enlarge.
With one right angle prism you can see around a corner. With two you can make yourself a real periscope.
Start with an empty paper towel roll or some heavy construction paper. Get a little cardboard or crumpled paper and some tape. Arrange the prisms as shown in the diagram to the left.
Take your periscope out and have fun!
Note: You can make rainbows with a right angle prism. Take your right angle prism outside on a sunny day and try it. If your primary purpose is to make rainbows, we recommend purchasing an equilateral prism. We offer an equilateral prism made from acrylic and another of crown glass which is suitable for making rainbows and more advanced optics experiments.
Size: 1¼" x 1¼" x 1¾" (3.2cm x 3.2cm x 4.4 cm)
Gift wrap orders: input salutation in the comment section at the end of the ordering process.