Fibre optics – the theory
A fibre optic strand is made from very clear glass and is extremely thin; between 125 to 250 microns in diameter. This is about the thickness of a single human hair. The fibre consists of a very thin core that has been fused with a thicker cladding.
To transmit data over long distances, light is sent through the fibre using a laser. The light enters the fibre at an acute angle relative to the outside surface, which causes internal reflection. As a result, the light stays in the fibre.
The speed at which the information can be sent depends on the laser. The faster it sends on and off signals, the faster the rate of data traffic.