The Fiber Optic Association - Tech Topics
Fiber Optic Project for a Science Fair Or Scouts
We have gotten many requests for projects involving fiber optic communications for science fairs, K-12 science classes and scout projects. We thought we'd share with you the project we developed for our own kids in the Scouts and has been used in several science fairs.
The project uses plastic optical fiber (POF) which has a larger core than glass fiber ( 1 mm ) and transmits best at 650 nm, or bright red light so it is easily visible. Our project uses a small red LED driven by a 9V battery. The diagram was drawn by Eric Habegger who contacted us for help through this web page, used our idea for his project, then drew this nice diagram on his computer.
The 100 ohm resistor limits the current through the LED and the momentary contact switch provides a means of modulating the LED light by turning it on and off. If you choose the smallest LED, a piece of plastic tubing (about 3/32 inch inside diameter) slipped over the LED and the endo f the fiber makes a perfect way to hold the LED firmly against the end of the fiber.
Your eye (or anyone's) becomes the receiver. You can see the light easily with your eye. Eric used his link to send morse code, normally received as sound.
You can buy most of the materials at Radio Shack or any electronic hardware store. If you can't find the POF itself, buy an inexpensive "TOSLINK" cable used for CD and DVD players and cut off one of the connectors. And feel free to send us email if you have questions.
Teachers: see our free online PPT presentation - an introduction to fiber optics.
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