Optical Fibre is used to transmit light between 2 ends of the fibre, a ‘waveguide’ or ‘light pipe’. It is very thin, around the thickness of a human hair, and made of transparent fibre made of glass or plastic. Optical fibre is sometimes known as Fibre Optics when used in science and engineering. Instead of using one metal wire the threads of fibre optics are but in bundles which transmit messages and images and other data. Fibre optic cables can carry more data than metal cables as well as being less susceptible to interferences, being lighter and thinner and faster. However they are very expensive and fragile. Nevertheless most telephone and internet companies are starting to use fibre optics instead of metal cables and soon most communications will be using fibre optics. It works by using total internal refraction, where the light reflects backwards and forwards internally along the whole length so the image can be communicated clearly from one end to another
In 1854, John Tyndall showed that light signal could be bent by demonstrating that light could be conducted through a curved stream of water. Next, in 1880 Alexander Graham Bell invented his ‘Photophone’. This transmitted a voice signal through a beam of light which worked very similarly to how a phone now works with electric signals. In 1888 a medical team in Vienna used bent glass rods to look inside the body. In 1895 a French engineer designed something similar to television which used bent glass rods to guide light images.
Over the years many people started to develop things increasingly similar to the fibre optics used today. In 1952, a physicist named Narinder Singh Kapany performed experiments that led to to the invention of optical fibre. A few years later the type of optical fibre we used today were invented where the fibre is coated with cladding that could make a better refractive index. After this, development focused on the bundles of fibre used for image transmission. In 1956, researchers in Michigan created the first semi-flexible gastroscope, used to look inside the body in operations. Jun-ichi Nishizawa, a Japanese society, started the idea of using optical fibres for communications on 1963.
Uses of optical fibres and the impact upon society
They are used in telephone cables and are faster and have a higher bandwidth than copper cables. As telecommunication demand increases we will be needing fibre optics more and more as it offers huge communication capacity. A much greater amount of information can carried through an optical fibre in comparison to a copper cable. They are also cheaper and thinner so therefore easier to install and maintain though the installation price is significantly higher than installing copper wires. Also, as signals go along a cable some energy is lost, however, with optical fibre the signal can be regenerated every 50 km instead of the 2 km of copper wires. On top of all this they do not cause electrical interference o or cause sparks that could cause explosions
Optical fibres are used in laproscopic surgery or keyhole surgery where a bundle of optical fibres, or an endoscope, is put down the patient’s body so the doctor can see the area he is operating on. They also allow doctors to see inside the patient’s body without having to perform surgery as it can be inserted through the mouth. Also they are used as bright lights that can be used by doctors.