Answers

The Brainliest Answer!
2014-10-01T17:23:07+05:30

This Is a Certified Answer

×
Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.

total internal reflection is the basic principle of the working of optical fibres.an optical fibre is very thin fibre made of glass or plastic fire having radius about a micrometer. A  bunch of such thin fibres form a light pipe.some of its uses are :1)all organs of the body are not visible to the naked eye and it can be seen through optical fibres by inserting into the mouth.light is sent down through the one set of the fibres in pipe.it illuminates the inside of the stomach.and can be seen on the computer screen.2)2000 telephone signals ,approximately mixed with light waves ,may be transmitted through a optical fibre.
12 4 12
2014-10-01T22:51:26+05:30

This Is a Certified Answer

×
Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
Optical fibre is a long cylindrical wire that consists of an inner core and a cladding layer on top of inner core. The inner core is made of a glass of higher refractive index as compared to the cladding core. The diameter of the inner core of a fibre is approximately 100 micro meters. The outer part of cladding is coated with a polymer. It protects fibre from breaking. Multiple fibres are put inside a protective sheathing in a cable. One fibre is used for communication in each direction. So cables have pairs of cables. 

In 1985-90 the fibre cables came in to a wide use. A cable was laid in 1990 between USA and England under the Atlantic ocean.

An electrical signal is converted into an optical signal by use of (transducer) optical LEDs. They glow at the frequency of the incoming signal. The LED is kept at one end of the fibre.

When a light wave is incident on the circular cross section of the fibre at one end, it is refracted on entering inner core and it is incident on the interface between inner core and the cladding. The angle is arranged to be more than the critical angle and so the light wave is reflected totally. into the inner core. The light wave travels along the fibre cable with innumerable number of total internal reflections.

When the light wave reaches the other side (receiver), the optical-diodes sense the light and convert the signal into electrical pulses. These pulses are given for digital processing.

Silica glass Optical fibres can transmit with very small loss of energy over kilometres. The fibres are flexible inside the covering material. Many fibres are packed together in to a cable.  Each fibre has a very large optical bandwidth and high response time. It is suitable for super fast transmission systems and for computer networking and for on board connections too. One fibre can be used to transmit waves of many frequencies simultaneously. 

One advantage of optical fibre is that they are electrically and  magnetically not affected by any external interference unlike copper wires. Multiple grades of the fiber is fabricated suitable for different applications.

These cables are some what expensive, but the advantages are many fold. So they are used in telecommunications. They are also used as table top decorative (colorful) lighting articles (fountain) made of plastic (cheap) fibre.  Their top ends are illuminated in bright colors. These cables are used to illuminate internal organs like esophagus, stomach and intestines.
19 4 19