The presentation discusses optical fiber cables, explaining their structure, working principles, advantages, disadvantages, and applications. Optical fibers are thin glass fibers that guide light for communication, utilizing total internal reflection, with classifications based on mode and refractive index. Despite high installation costs and limitations, optical fibers offer immense bandwidth and are crucial in various sectors including telecommunications and medicine.

1. PRESENTATION
ON
OPTICAL FIBER CABLE
Presented by :
Huzaifa Bin Nawab 2480181
Mubarrah Naeem 2480220
Zia Ullah 2480227
Abdul Moiz bin Irfan 2480167
Fatima Batool 2480245
Submitted to:-
Miss Aqsa Raees

2. Brief flow of presentation
• Introduction
• What are Optical Fibers ?
• Structure of optical fiber
• Working principle of optical fiber
• Optical fiber communication system
• Advantage / Disadvantage of optical fiber
• Application of optical fiber
• Conclusion

3. What is Optical Fiber ?
• An optical fiber is a hair thin cylindrical fiber of glass
or any transparent dielectric medium.
• The fiber which are used for optical communication
are wave guides made of transparent dielectrics.
• Its function is to guide visible and
infrared light over long distance.

4. Structure of optical fiber

5. Conti…
• Core- central tube of very thin size made up of
optically transparent dielectric medium and carries
the light form transmitter to receiver. The core
diameter can vary from about 5um-100 um.
• Cladding- outer optical material surrounding the
core having reflecting index lower than core. It
helps to keep the light within the core throughout
the phenomena of total internal reflection.
• Buffer Coating- plastic coating that protects the
fiber made of silicon rubber. The typical diameter
of fiber after coating is 250-300um.

6. Working principle
• Total Internal Reflection(TIR)
• When an ray of light travels from a denser to a rarer medium such that
the angle of incidence is greater than the critical angle, the ray reflects
back into the same medium this phenomena is called TIR.
• In the optical fiber the rays undergo repeated total number of
reflections until it emerges out of the other end of the fiber, even if fiber
is bend.

7. Classification of optical fiber
• Optical fiber is classified into two categories based on:-
1) The number of modes-
 Single mode fiber(SMF) and
 Multi-mode fiber(MMF)
2) The reflective index-
 Step index optical fiber
 Graded- index optical fiber

8. On basis of number of modes:-
Single mode fiber-
 In single mode fiber only one mode can propagate through the fiber.
 It has small core diameter (5um) and high cladding diameter (70um).
 Difference between the refractive index of core and cladding is very
small.
 There is neither dispersion nor degradation therefore it is suitable
for long distance communication.
 The light is passed through the single mode fiber through laser
diode.

9. Multi- mode fiber
It allows a large number of modes for
light ray travelling through it.
The core diameter is 40um and that of
cladding is 70um.
The relative refractive index difference
is also large than single mode fiber.
There is signal degradation due to
multimode dispersion.
It is not suitable for long distance
communication due to large
dispersion and attenuation of signal.

10. On the basis of refractive index
• There are two type of optical fiber:-
1) Step index optical fiber
2) Graded- index optical fiber

11. Single Index fiber:-
Step-index optical fiber-the refractive index of core and
cladding are constant.
The light ray propagate through it in the form of
meridiognal rays which cross the fiber axis during every
reflection at the core cladding boundary.
Graded Index Fiber:-
In this type of fiber core has a non uniform refractive index
that gradually decrease from the center towards the core
cladding interface.
The cladding has a uniform refractive index.
The light rays propagate through it in the form of helical
rays. They never cross the fiber axis.

12. Optical Fiber Communication
System

13. • Information Source:
Generates the information to be transmitted (e.g., voice
data, video).
• Electrical Transmitter:
Converts the information signal into an electrical signal.
• Optical Source:
Converts the electrical signal into an optical signal (light
Typically uses a laser or LED.
• Optical Fiber:
Transmits the light signal over long distances with minim
loss.

14. • Optical Detector:
Converts the received light signal back into an electrical
signal.
• Electrical Receiver:
Demodulates the electrical signal to recover the original
information.
Amplifies the signal if necessary.
• Destination:
Receives the recovered information and processes it further.

15. Advantage of Optical Fiber
 Immense bandwidth to utilize
 Total electrical isolation in the transmission medium
 Very low transmission loss
 Small size and light weight
 High signal security
 Very low power consumption and wide scope of system expansion
etc.

16. Disadvantage
1) System installation is very costly.
2) Only point-to-point communication is possible.
3) Precise and costly instruments would be required.
4) Splicing is time consuming.
5) It accept only unipolar codes.

17. • 1. Fragility
• 2. High installation cost
• 3. Limited bend radius
• 4. Requires specialized equipment
• 5. Susceptible to environmental factors.
Limitations:

18. Applications
• Optical fiber have wider range of
application in almost all field,
some are specified below:-
• In telecommunication field
• Civil, consumer and industrial
application
• In military applications
• Broadband applications
• In decorations, etc.

19. The Endoscope(In medical field)
There are two optical fibers in endoscope:
1) One for light, to illuminate the inside of patient.
2) Another for a camera to send the images back to
doctor.

20. Conclusion
At the last, there are some negatives of using
optical fiber communication system in terms of
splicing, coupling, set up expenses etc. but it is an un
avoidable fact that optical fiber has revolutionized the
field of communication. As soon as computers will be
capable of processing optical signals, the total arena
of communication will be opticalized immediately.