The advancement of Medical Science, Development of many instruments, Equipments for modern life to be comfortable was and is, and will always be dependent on the progress of Electronic and computer technology. It is essential for the academicians, scientists and engineers, student of science technology to develop their interests and exchange their technical knowledge and enhance their communication and presentation skill for the development and redefine the course of science and Technology of the society. On the eve of seminar on the well famous topic of today since “Symposium on Contemporary electronics and computer Technology’’, I am going to throw some light on the topic ‘The Gift of Optical Fibre Communication to Modern Life.’

Optical Fibres are the hair like very fine glass fibres inside which the light signals can travel. Actually they act for light frequencies, as wave guides act microwaves, but they have advantages over wave guides. Optical frequencies, being of the order of 1015 Hz are much greater than microwaves (1010 Hz) so light beams when used as a carrier wave for sendug information, is capacity of an optical fibre is much greater than microwave systems. In other word multiple routes may be compressed in a much smaller cable. The basis material for glass fibre is silicon dioxide which is quite abundant on the Earth. The fibre cables are strong and flexible; they have smaller and lighter weight. They do not break even if wrapped in curves of very small radius. This helps on their transportation and installation.

Techniques have been developed for the production of fibres with very low transmission losses about 0.2db/km. The most important advantage of fibres, they have ability to carry large amount of information in either digital &analog form. In a recently developed fibre optic system, it has been possible to send

capsule endoscopy foe examination of the small bowel. High magnification endoscope for detection of minute lesions and confocal microscopy to obtain histrogical at endoceopy. Everyman’s Science (vol.XL.No .3 Aug. Set. 2005).

The optical fibres can carry light along curved paths by the process of total internal reflection of the light and hence transmit images round the corners. Optical fibre are being used a technique called ‘endoscopy’ to examine the human body organs. This also helps in conducting surgical operations. Optical fibre is being used in telecommunications like telephones. An optical cable cans hundreds of telephone conversation through it at the same time.

The emitter is usually on LED or semiconductor laser. Whilst the detector may be a pin or avalanche photodiode. Repeater until may be necessary over relative long links to counter the effects of fibre transmission losses and dispersion. In these, the signal is detected, amplified and then re-emitted. For digital signal it is possible to restore distorted digital signal pulse to its original shape, whilst with analog signal distortion or noise present it, of necessity passed on. A separate power supply line must be providing for these until. The presence of repeators greatly adds to the cost of a link.

The main advantage of optical fibre links includes relatively low attenuation at optimum wavelengths, high band width (up to several gigahertzes), small physical size and weight. The elimination of ground loop problems and immunity from electrical interference. This latter advantage is especially useful in electrically noisy environments such as densely populated urban areas and power stations. There is of

140Mbits/sec.Information through a 220 km link of one optical fibre which is equivalent to about 4,50,000 voice channel-km.Band width of optical fibre which is equivalent wire transmission line. The number of signals that can be modulated on a fibre optical light beam exceeds the number that can be modulated on a very high frequency R.F carrier by a factor about 1000. Optical fibreglass or plasters are due to external radiator striking the fibre. The fibre is well protected from interference and not radiate energy within them; therefore it is difficult to detect the signal being transmitted. As such they offer a degree of Security and Privacy.

Optical fibre are extensively used in telecommunications, surgical operation etc.great progress has been made in making optical fibres which can guide light, and thus transmit images round corners. This fibre is used in endoscopy to examine the internal human organs.

In 1868 oesophascope and gastro scopes (half meter long pipe fitted with a light and lenses) were introduced. Light conduction was a formidable obstacle for endoscopes. It was solved when transmission along aligned bundles of specially coasted flexible glass fibres was achieved by H.H.Hopkins & Kapany NS-A flexible fibre scope, using static scanning. Nature (Lond) vol.173 p 39-41 1954. In 1954 Hopkins and Kapany summarise of their achievement and introduced new terminology an optical until comprises a bundle of fibres of glass or other transpararent materials, and it therefore appears approximate to introduce the term ‘Fibrescope’ to denote it. An ovious use of the until is to replace the train of lenses employed conventional endoscopes.

At present, endoscope some with electronic devices like video, are used extensively for both diagnostic and therapeutic purpose. Many more ingenious developments and applications of the technology are currently at the point availability viz. wireless

course, no spark hazard-an additional advantage in explosive environments such as chemical plants. The telephone networks require links capable of carrying many signal channels simultaneously. Digital transmission is able to cope with this easily science the separate bit streams required may be interleaved. In both the united state and Europe, standard rate have been agreed upon for various ‘levels’ of transmission.

There are numerous other potential applications including for example, undersea links, video transmission, computer links and the military sphere. Missile guidance, several pilot experiments have been run to examine the feasibility of providing the whole of community’s communication information need (such as telephone, T.V., Radio etc) using fibre opticals.

Thereby my concluding wards I want to state that whole society should have knowledge about the technology to develop various uses of optical fibres as its raw materials are very cheap and easily available. Reference:-

(i) Opto electrons:-J.Willson JFB Hawkes
(ii) H.H.Hopkins & Kapany N.S.A fexible scope using static scanning nature (lond)
Vol.173p 39-41.
(iii) Everyman’s science Vol.XL No.3 Aug – Sept. 2005.
About the Author: Dr. Taran Kumari Roy is Reader in the University Deptt.of Physics B. R. A. Bihar University, Muzaffarpur (Bihar)

About the Author: Dr. Taran Kumari Roy is Reader in the University Deptt.of Physics B. R. A. Bihar University, Muzaffarpur (Bihar)