The fibre of communications

With the coming of the fibre optics revolution, information can now be transmitted at the speed of light. At the heart of this revolution is a glass or plastic fibre no thicker than a human hair. A fibre optic cable often only as thick as a pencil can carry a great deal more telephonic and electronic information than conventional cables. This information is carried as light flashes. The electronic information is first converted to light signals with a transmitter device known as a laser diode or a light emitting diode.

At the receiving end, another piece of equipment known as a photodiode converts these light signals back into electronic signals. Because signals are carried at optical wave lengths, or as light, at extremely high frequencies, a great deal more information can be carried.

In India, all the trunk telephonic routes are linked by optical fibres, and eventually copper cables linking individual subscribers will also be replaced with optical fibres.