Photo courtesy Corning
A fiber-optic wire

You hear about fiber-optic cables whenever people talk about the telephone system, the cable TV system or the Internet. Fiber-optic lines are strands of optically pure glass as thin as a human hair that carry digital information over long distances. They are also used in medical imaging and mechanical engineering inspection.

In this article, we will show you how these tiny strands of glass transmit light and the fascinating way that these strands are made.