Fibre Optics – An Introduction

Fibre optics are extended strands of glass pure enough to allow light to pass through them and also as thin as a human hair. Fibre optics are made up of three different components, the core (made of glass), the cladding (a material which surrounds the glass core and reflects light) and the buffer (a coating, typically made of plastic that protects the core). Normally these three parts combine to make a single fibre optic strand, thousands of which are bundled to form cables.

There are also two major types of fibre optics labelled as single and multi mode fibres. A single mode fibre is the smaller of the two and has a diameter of around 9 microns, whilst the latter, multi-mode fibres are much larger and can have diameters of around 62.5 microns. The diameter difference allows the different types of fibre optics to carry lights of differing wavelengths. As well as glass fibres there are even fibre optics manufactured using special plastics, these typically have the largest diameters.

Fibre optics work by transporting light. Making light go in a straight line however is simple; it is when it must travel round corners that difficulties arise. This is where fibre optics come in, through reflecting light internally the same light can be shone down the length of the fibre, around corners, under mountains, across oceans, wherever you need it to go.  Fibre optic sensors use a principle named total internal reflection, ensuring that light passes along the length of the fibre without loss. Impurities in the glass will typically lead to some light degradation, particularly over huge distances, which is why relay stations are employed to ensure fidelity is maintained.

There are significant advantages to using fibre optics, including:

Because of these advantages fibre optics have been used in myriad applications. From connecting your home computer to the internet, usage within medical operations to sensors in planes and along pipes which span continents fibre optics have certainly laid their mark upon the world of commerce and industry within the modern, digital age.