It is no over statement to say that fibre optic cables have revolutionised the world we live in. These cables contain numerous optical fibres that are designed to guide light along the length of the cable. The science behind how these cables are used to convert information is made up off a combination of applied science with engineering. Engineers have used the theories developed by scientists and have turned it into a practical device that is used in a wide variety of data transfer situations.

There are a number of different benefits of fibre optic data transfer. The major one is that data rates across fibre optics are very quick and as a result a large amount of data can be transferred over long distances quickly. They also improve on metal wires in that they are immune to electromagnetic interference and they experience less loss than metal wires.

Fibre optic cables are used in a huge range of scenarios such as sensors and for communications. At the core of the fibre optic is light. As the name optic suggests the optical fibre essentially works by sending a light signal down a cable. The way in which this is done is through a process of total internal reflection which in short bounces the light down the fibre in a sophisticated way that makes the light signal readable.

The fibre works as a waveguide and the way in which the light is sent down the cable effects the signal it gives at the end. There are a number of different types of fibres that support different numbers of propagation paths. Multimode fibres (MMF) support a number of different paths and fibres that support single mode paths are called single mode fibres (SMF). The multimode fibres are generally utilised with communication systems that extend to a maximum of 200 metres. For communication links that are longer than 200 metres the single mode fibre is used. This is because the multimode fibres are used where high power must be transmitted.

One of the drawbacks of fibre optic cables is that connecting them to one another or other communications devices is much harder than making a connection between an electrical wire or cable. The reason that connecting optical fibres is more complex than electrical wires is that the connections that are made between fibre optic cables need to be much more precise. The cable needs to be spliced in such a way that the ends of the fibres are not damaged and that they can be reconnected elsewhere. If they are sliced apart effectively then the ends of the cables can be fused together using an electric arc. Special connectors are used to make connections that can be moved so that it is easier to connect, disconnect and move a connection.

The scientific theories that guide the use of fibre optic cables date back over a hundred and fifty years to the 1840s when Daniel Colladon and Jacques Babinet demonstrated the principles. An Irish inventor called John Tyndall took the principles further and gave public displays using water fountains. The technology was subsequently used to help dentists illuminate the mouth to make surgical procedures in dentistry easier and the theories were used to develop lighting methods that were used for internal medical examinations.