It is a
communication technology to carry data and information along a glass fibre by
use of light. What is fiber optics? Fibre optic is a long, thin strands of pure
glass and diameter of fibre optics is so small as about the diameter of human
hair. Fibre optics is used to transmit the light signal along a long distance .Fibre
optical communication system revolutionized the telecommunication. Optical fibre
have replace copper wire communication in core networks in the developed world
because of its advantage over electrical
transmissions. Optical fibre uses in telecommunication companies to transmit
telephone signal, cable television signal, internet communication. Fibre optic
has the 3 parts, the name of these parts is
Core -
Thin glass centre of the fibre, the part where the travels light.
Cladding
– An outer optical material that surround the core. It reflects the light back into the core.
Buffer
coating –A plastic coating that protects the fibre from damage and also protect
from moisture.
Optical fibres come into two types.
1: Single mode fibre
2: multi - mode fibre
Single mode fibre:-
Single
mode fibre optic cable has a core of small diameter in which only one mode of light
propagate. As light passes through the core, creation of number of light reflection
is decreases lowering the attenuation
and increasing the ability for the signal to travel faster and for long
distances .This is used in telecommunication companies , colleges and
universities.
Multi-mode fibre
Multi –
mode fibre optic cable has a core of large diameter in which multi mode of
light propagate.
As light
passes through the core, creation of number of light reflection is increases. The
ability for more data to pass through at a given time increases. Because of a high
dispersion and attenuation, the ability for the signals to travel over a long
distances decreases. This is used in audio or video application in LANs.
How
optical fibre transmit light??? The
light in fibre optic cable travels by uses of principle of total internal
reflection that is light travel through the core by constantly bouncing from
cladding. Purity of glass and wavelength of light determine the extent of the
signal degraded.
Fibre optics transmission system:
It
consists of following:
1
-transmitter: It produces and encodes the light signal
2
-optical fibre: conduct the light signal
3 -optical
regenerator: necessary to boost the light signal for long distance
4 -optical
receiver: receives the light signal and decode it.
Advantages of fibre optics:
1-Less
expensive
2-Thinner
3-Higher
carrying capacity
4-Less
signal degradation
5-Light
signal
6-Low
power
7-Digital
signal
8-Non-flammable
9-Lightweight
10-Flexible
Disadvantages of Fibre optics:
1-Expensive
2-Require
more protection
3-Fragile
4-Transmission requires repeating at distance intervals.
