Saturday Rave: optical fiber

On 22 April 1977 fiber optic cable was first used to send telephone messages.

Happy fortieth birthday!

A great deal more than I know about fiber optic cable can be found in the relevant wikipedia entry, but what I can tell you is that it's pretty cool stuff. It's basically a long piece of glass just a bit thicker than a human hair (as a matter of fact a clear human hair will work in rather the same way) that reflects information along it as far as you like without losing very much of it at all.

Why the glass fibre doesn't break I have no idea at all, but what I do know (thanks again, wikipedia) is that a single fibre can carry 90,000 TV channels (the mere thought of this turns me quite faint). 

And that isn't the end of its cleverness, because information in the cable isn't upset by any sort of outside interference (which can be a problem with metal wires): fibres are indifferent to electricity, so you can put them in the same holes as electricity cables; fibres tend to stay in the hole once you've put it there because people don't want to steal the fibre in the way they'll steal copper; you can't tap a fibre line the way you can a copper one; and optical fibers are jolly useful if you want to look into a small space (like a human body via an endoscope).

There. That's all I know - and much more than I understand.

But it's clearly very nearly a miracle, isn't it.

Word To Use Today: fibre. (Or fiber.) This word comes from the Latin fibra, which means filament - or charmingly, entrails.