Fibre Optic

Fibre-optic cable allows data to be transimitted by making use of light.

The cable has an extremely transparent central glass core, which is surrounded by cladding. When light enters the central core, it cannot get out until it reaches the other end because the cladding reflects the light - so effectively fibre-optic cable is a guided-light pipe.

A fibre-optic system works as follows

• The data is mixed (modulation) with the carrier light beam
• The beam is injected into the fibre-optic cable
• At the other end of the cable, a photo-detector senses the light and converts it into a normal electrical signal
• The signal is passed into an electronic demodulator to extract the original data

2020-10