Optical Fibre : A boon for Today's Technology
Let’s know how this works:
Optical fiber or Fiber Optics is the medium and the technology associated with the
transmission of information as light pulses along a glass or plastic strand or
fiber. Fiber optics is used long-distance and high-performance data networking.
But the question is
how this light tavels through wire ?
Now let me ask a question that have you ever heared about
total internal reflections?
For those who don’t know let me explain first :
When the light is incident on a reflecting surface , it
reflects in a certain direction. The phenomenon of Total Internal Reflection
occurs if the angle of incidence is greater than a certain limiting angle,
called the critical angle. In general, total internal reflection takes place at
the boundary between two transparent media when a ray of light in a medium of
higher index of refraction approaches the other medium at an angle of incidence
greater than the critical angle. For a water-air surface the critical angle is
48.5°. Because indices of refraction depend on wavelength, the critical angle
(and hence the angle of total internal reflection) will vary slightly with
wavelength and, therefore, with colour. At all angles less than the critical
angle, both refraction and reflection occur in varying proportions.
Now let us Talk about
how this happens in Optical Fibre :-
When light passes from a medium with one index of refraction
(m1) to another medium with a lower index of refraction (m2), it bends or
refracts away from an imaginary line perpendicular to the surface (normal
line). As the angle of the beam through m1 becomes greater with respect to the
normal line, the refracted light through m2 bends further away from the line.
At one particular angle (critical angle), the refracted
light will not go into m2, but instead will travel along the surface between
the two media
If the beam through m1 is greater than the critical angle,
then the refracted beam will be reflected entirely back into m1 (total internal
reflection), even though m2 may be transparent!
In an optical fiber, the light travels through the core (m1,
high index of refraction) by constantly reflecting from the cladding (m2, lower
index of refraction) because the angle of the light is always greater than the
critical angle. Light reflects from the cladding no matter what angle the fiber
itself gets bent at, even if it's a full circle!
Because the cladding does not absorb any light from the
core, the light wave can travel great distances. However, some of the light
signal degrades within the fiber, mostly due to impurities in the glass. The
extent that the signal degrades depends upon the purity of the glass and the
wavelength of the transmitted light.
What are the
Practical uses of Optical Fibre?
optic cables are cables that contain several thousand
optical fibers in a protective, insulated jacket. The optical fibers are very
thin strands of pure glass, which transmit information in the form of light.
Fiber optic cables have revolutionized the world of network communication ever
since their inception nearly four decades ago. Today, these cables have almost
obliterated traditional methods of networking, which use metallic wires by
providing higher bandwidth and transmitting data over greater distances. Some
of the most popular uses of fiber optic cables are listed below.
a. Internet
Fiber optic cables transmit large amounts of data at very
high speeds. This technology is therefore widely used in internet cables. As
compared to traditional copper wires, fiber optic cables are less bulky,
lighter, more flexible, and carry more data.
b. Cable Television
The use of fiber optic cables in the transmission of cable
signals has grown explosively over the years. These cables are ideal for
transmitting signals for high definition televisions because they have greater
bandwidth and speed. Also, fiber optic cables are cheaper as compared to the
same quantity of copper wire.
c. Telephone
Calling telephones within or outside the country has never
been so easy. With the use of fiber optic communication, you can connect faster
and have clear conversations without any lag on either side.
d. Computer Networking
Networking between computers in a single building or across
nearby structures is made easier and faster with the use of fiber optic cables.
Users can see a marked decrease in the time it takes to transfer files and
information across networks.
e. Surgery and Dentistry
Fiber optic cables are widely used in the fields of medicine
and research. Optical communication is an important part of non-intrusive
surgical methods, popularly known as endoscopy. In such applications, a minute,
bright light is used to light up the surgery area within the body, making it
possible to reduce the number and size of incisions made. Fiber optics are also
used in microscopy and biomedical research.
f. Lighting and Decorations
The use of fiber optics in the area of decorative
illumination has also grown over the years. Fiber optic cables provide an easy,
economical and attractive solution to lighting projects. As a result, they are
widely used in lighting decorations and illuminated Christmas trees.
g. Mechanical Inspections
Fiber optic cables are widely used in the inspection of
hard-to-reach places. Some such applications are on-site inspections for
engineers and also inspection of pipes for plumbers.
h. Military and Space Applications
With the high level of data security required in military
and aerospace applications, fiber optic cables offer the ideal solution for
data transmission in these areas.
i. Automotive Industry
Fiber optic cables play an important role in the lighting
and safety features of present-day automobiles. They are widely used in
lighting, both in the interior and exterior of vehicles. Because of its ability
to conserve space and provide superior lighting, fiber optics are used in more
vehicles every day. Also, fiber optic cables can transmit signals between
different parts of the vehicle at lightning speed. This makes them invaluable
in the use of safety applications such as traction control and airbags.
Therefore Optical Fibre proved to be very useful in every
technical field.
Stay Tuned J
Thank You !
Good
ReplyDelete