Fibre Optics Facts - Mocomi Kids

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FIBRE OPTICS

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FIBRE OPTICS

You may have heard about fibre optics but the name itself does not decsribe much about this fascinating technology. The term is used to refer to the technology where the energy of light is harnessed to transmit data, much like you would use an electric impulse in a copper wire. Since light travels at the speed of 300,000 kms per second, fibre optic technology has greatly reduced the speed at which information can be sent and received. F UN FOR ME!

OPTICAL FIBRES

FIBRE OPTICS

An optical fibre is a semi-flexible, transparent, and extremely thin strand of pure glass that has the diameter of a human hair. Thousands of these strands are arranged in bundles to make a thicker cable. Since glass is optically transparent we are able to send informationladen rays of light over long distances. A fibre optic cable is made up of five parts: Strands of glass that are bundled together to make one single channel F UN FOR ME!

FIBRE OPTICS

of light called makes up the core. The diameter of the core dictates how much information can be sent and received at once. A protective sheath or coating around any structure or material is known as the cladding. In fibre optic cables the silica cladding increases the total internal reflection of the core. Therefore a light pulse can pass through the entire length of the fibre with little data loss. F UN FOR ME!

FIBRE OPTICS

A layer of plastic surrounds the core and cladding to reinforce the fibre core. The coating provides extra protection and prevents the cable from bending too much. The strengthening fibres around the coating give added support to the coating especially when it comes to stretching tension. F UN FOR ME!

FIBRE OPTICS

Finally all this is covered in the cable jacket like any other cable or wire. The only part of a fibre optic cable that carries data is the tiny core in the centre but it has layer upon layer of protection because glass is extremely brittle and in order for it to function at its best, there can be no breaks in the fibre at all. Add to that the high cost of producing them and you will know why every precaution must be taken to prevent damage. F UN FOR ME!

TOTAL INTERNAL REFLECTION

FIBRE OPTICS

If you shine a torch down a long hallway, you will see that light travels in straight lines to the end of the hallway. Now if there was a bend in the hallway, you could put a mirror at the bend and light would be reflected to change direction and continue down the bend. But what if this hallway had many twists and turns and it was up to you to shine light from where you are standing to the end of the hallway? F UN FOR ME!

FIBRE OPTICS

You could set up an elaborate system of mirrors so that light will keep reflecting until it reaches the end. A fibre optic cable is able to do this, not with the help of an elaborate set-up of mirrors, but because of the phenomenon of total internal reflection. Think of the cladding as the many mirrors along the walls of the hallway of fibre continuously reflecting light. In this way the light is contained within the core and continues along its path inside the cable without degrading. F UN FOR ME!

HOW IT WORKS

FIBRE OPTICS

The first step in relaying information over a fibre optic cable is the transmitter. The transmitter is responsible for converting an electrical digital signal into a light signal. It imprints the information onto the light as changes in intensity and pulse rate. If the ray has to travel a long distance, it will have to pass through an optical regenerator. This nifty device re-boosts the strength of the ray by copying the message and sending a duplicate onward to its destination. A message may have to pass through multiple optical regenrators along its path. F UN FOR ME!

FIBRE OPTICS

Finally the ray of light, with the message imprinted on it arrives at the optical receiver. Here it is decoded back into a binary digital format.

USES The most common use of fibre optics is in the field of communication. Massive amounts of data is sent and received over networks of fibre optic cables for various industries such as cable television, phones, and the internet.

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FIBRE OPTICS

Since these cables are able to bend, doctors use them during surgery to shine light inside parts of the body which are hard to reach. Fibre optic scopes are also used by engineers and mechanics to throw light onto parts of machines with a lot of twists and bends where light cannot easily travel. It is also used for imaging in hard to reach areas or places with extreme conditions such as deep underground, under the sea or inside the body. F UN FOR ME!

FIBRE OPTICS

CONCLUSION Fibre optic cables have communications industry.

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Before its invention, we relied on copper wires carrying electrical signals. Data would diminish while traveling over the ancestors of fibre optic cables and sometimes even get lost completely. These flexible, light-weight, non-flammable, low-power cables may be expensive but are definitely worth their weight in salt. F UN FOR ME!

FIBRE OPTICS

PROJECT

How does a binary signal differ from an analog signal? Doctors use fibre optic scopes when they perform a particular type of surgery called a laproscopy. Can you find out what this technique of surgery is and how a fibre optic scope is beneficial? Find out whether total internal reflection is possible with materials other than glass.

Image Source: www.wikipedia.org All images are public domain, sourced from the wikipedia commons

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