Splicing

Optical Fibres are layed over long distances.Mostly the optical fibre cables are available in drums of 2 km,4 km etc.So at each 4 km there will be a joint.This jointing method here used is called splicing.There are two types of splicing one is the mechanical splicing and the second one is the fusion splicing.The fig here shows mechanical splicing method.This is a quick method and the fibers won't be permanently joined,only precisely held together,so that light can pass through it very easily.The second method is fusion splicing ,here permanent joint is made between two fibers,Lot of patience and care is needed for this splicing.First we have to prepare the cable for splicing.The steps involved are

1. Remove the outer jacket of the cable using sheath remover to a required length.
2. Remove the inner jacket of the cable using sheath remove(both are similar)
3. Cutoff the strength member up to the required length.
4. Cut off the dummy buffers up to the required length.
5. Clean the jelly filled using Iso Propyl Alchol.
6. Remove the buffer tubes using Buffer tube remover.
7. Clean the jelly filled using Iso Propyl Alchol.
8. Remove the primary Coating using Primary Coating Stripper or Fiber optic stripper.
9. Clen the jelly filled using Iso Propyl Alchol until a knocking sound is heard.
10. Prepare the 2 ndcable also like this
11. Bring them near the Splicing machine.
12. Using the cleaver available in the machine do a perfect vertical cut in the two fibers
13. Place the fibers in the v-groove correctly
14. close the lids
15. Fuse the fibers
16. note the loss

Fiber optics Basics

Optical fiber communication is made successful with the invention of optical fiber cables,which is readly available as the raw material is sand or silica.The opticalfiber consist of a core and a cladding.Core have high refractive index than cladding,but the difference is only small. It works on the principle of total internal reflection .When the light travels from denser medium ,if the incident angle is greater than a particular values(it is called critical angle.) all the light will be reflected.This is called total internal reflection.Critical angle is the angle of incidence above which total internal reflection occuurs.There are two types of fibers single mode and multi mode,For carrying light over long distances we opt only single mode fibers . Also multimode fibers suffer losses like modal dispersion which affects the bandwidth carrying capacity.Multimode has large core diameter,also less precise.

Components

The Fiber optical cable comprises of an outer jacket(usually orange coloured),inside that there will be an inter coveringof black color.Inside that there will be binder which will be of plaster or yarn.Inside that the buffer tubes will be there.mostly all the buffer tubes wont be filled with fiber,some will be empty they are called fillers or dummy buffer tubes.Along with that there will be a srength member which will be made of glass reinforced plastic or fiber reienforced plastic.It will give the fiber proper strength from breaking while we bend the cable.Inside the buffer tubes there will be optical fibers.They will be coated with an acrylic coating called primary coating.when we remove that we get bare fiber.

Usually the optical fiber cables will be available in bundles of 2 km 4 km...For long distance cable laying we have to join the cables after 2 kms...This process we are using is called Fiber Splicing.

Magic of optical Fiber

Cost of almost Everything in the universe goes on increasing...but take the case of telecommunication,whether it is increasing or decreasing,yeh sure its decresing day by day.But the facilities are increasing.Also the users are also increasing day by day.Can any one say why the rate of communication or the tariff in coming down? People may say its competition,but thatis not true coz in almost fields there is competition and the price is going up.ITs the magic of optical fiber that helps this low cost communication possible with high quality and latest facilities.