Exhaustive info on POFs including comparison with gglass optical fibers, processing techniques, Materials used, Future aspects etc

1. POLYMER OPTICAL
FIBERS
BY:-
Harshit Agarwal.

2. TOPICS TO BE DISCUSSED
 Introduction
 Principle Of Optical Fiber Communication
 History Of Polymer Optical Fiber
 Comparison of Polymer and Glass Optical Fiber
 Classification Of Pofs
 Materials Used In Pofs
 Application Of Pofs
 Fabrication Of Pofs
 Fabrication Of Si- Pofs
 Fabrication Of GI- Pofs
 Polymer Optical Fiber
 Plastic Optical Fiber Passive Devices
 Future Aspects Of Pofs
 Potential Of Pofs

3. INTRODUCTION
 An optical fiber (or optical
fiber) is a flexible, transparent
fiber made by drawing glass or
plastic to a diameter slightly
thicker than that of a human
hair. Optical fibers are used
most often as a means to
transmit light between the two
ends of the fiber and find wide
usage in fiber-optic
communications, where they
permit transmission over longer
distances and at
higher bandwidths
 Plastic optical fiber (POF)is
an optical fiber that is made out
of polymer. Similar to glass
optical fiber, POF transmits
light (for illumination or data)
through the core of the fiber.

4. PRINCIPLE OF OPTICAL FIBER
COMMUNICATION
Principle of operation
- Total Internal
Reflection
OPTICAL FIBER

5. HISTORY
 First introduced in 1960 by Dupont at nearly the same time
Glass optical fibers were introduced.
 Faced problems of very high attenuation of the order of 1000
dB/km.
 Application in communication almost impossible.
 Mitsubishi Rayon, Japan improved Dupont’s technology to
reduce attenuation to 300dB/ km but still quite high value.
 In 1980 Graded Index POFs were introduced.
 New processing techniques such as swollen Gel
Polymerization helped reduced attenuation problem
considerably.
 In mid 1990s the use of POFs for short distance high speed
communication were introduced.

6. COMPARISON B/W POFs & GOFs
POLYMER OPTICAL FIBER
 Plastic optical fiber, polymer
optical fiber is an optical fiber
which is made out of plastic.
It comprises of PMMA as the
core that facilitates the
transmission of light, and
fluorinated polymers as the
cladding material.
 Simpler and less expensive
components.
 Greater flexibility and light
weight.
 Bit rate upto 10Gbps.
GLASS OPTICAL FIBERS
 Glass optical fiber, just as its
name shows, is an optical
fiber made of glass. Being a
delicate type of optical fiber,
it cannot be cut, spliced or
repaired.
 Difficult handling and
delicate.
 Less resistant to flexibility
and accidental breakage.
 Higher information
transmission capacity & lower
losses.

7.  Used in low speed
and short distance
applications (upto
100 m).
 Generally in car
networks, home
networks, industrial
networks etc.
 Used in longer
distance
transmissions at
higher speeds.
 Under ground data
transmission systems
etc.

8. TYPES OF POLYMER OPTICAL
FIBERS
PLASTIC
OPTICAL FIBRES
(POF)
STEP INDEXED
PLASTIC
OPTICAL FIBRES
GRADED
INDEXED
PLASTIC
OPTICAL FIBRES

9. STEP INDEX POLYMER
OPTICAL FIBERS
A step index plastic optical fibre has a simple structure of a concentric
core and cladding. Consequently rather simple methods can be used for its
fabrication

10. GRADED INDEX POLYMER
OPTICAL FIBERS
GI POFs has drawn considerable interest recently as a high band width
data transmission medium for short distance application .

11. MATERIALS USED IN POFs
PMMA
 PMMA are used as the core, with
refractive indices of 1.49.
 Generally, fiber cladding is made
of silicone resin (refractive index
~1.46).
 High refractive index difference is
maintained between core and cladding.
 High numerical aperture.
 Have high mechanical flexibility and
low cost.
 Industry-standard step-index fiber has a
core diameter of 1mm.
 Attenuation loss is about 1 dB/m @ 650
nm.
 Bandwidth is ~5 MHz-km @ 650 nm.
FLUORINATED POLYMERS
 Fluorine (F) has a greater mass than
both H and D, allowing for lower
attenuation, theoretically approaching
that of silica glass fiber.
 Fluorinated polymers such a s poly tetra
fluoro ethylene or Teflon) typically form
the crystalline structures.
 Random copolymers result in the least
amount of crystallization.

12. APPLICATIONS
Currently the application of POFs can be
divided into four major categories:
 Lighting
 Communications.
 Sensors.
 Automobiles.

13. LIGHTING
 Decorations- lamps
and pools.
 Inspection of
mechanical welds in
pipes and engines
(airlanes, rockets and
automobiles).
 Medical
applications-
Endiscopes,
Bronchoscpoes,
Laproscopes

14. COMMUNICATION
•Research is being conducted to
reduce attenuation and increase
bandwidth to increase usage in
long distance communication.
•Ideal for short distance
network cabing
- New standard for LAN
cabling.
-Material cost fall between
copper and glass.
-Ease of installation.
•Gigabit Ethernet- Transport of
1.25Gbit/s Ethernet traffic over
900 m has been demonstrated
successfully.

15. SENSORS
 Optical measurement of flow, biofilm growth, toxicity, rotation,
humidity, fluoroscence.
 Humidity measurement
 - POG with PVA film.
 -Oil insulated power equipment.
 Toxicity biosensors.
- The fluoroscence produced by biological reaction is collected and
transmitted by POF.

16. AUTOMOBILES
•The number of electronic devices in
a car increases year by year,
primarily due to an increase in the
entertainment equipment desired for
modern passenger cars.
•This ubiquitous connection need is
a huge problem in networking
system designs for automotive
fiber from the viewpoint of both
physical space and system load.
Consequently, POF is specified in
the MOST standard to achieve the
lowest overall system weight and
easiest connectivity

17. FABRICATION OF POFs
STEP INDEXED
POLYMER
OPTICAL FIBRES
Continous Extrusion
Method
Preform Method
GRADED INDEXED
POLYMER
OPTICAL FIBRES
Photo-
Copolymerisaton
Swollen Gel
Polymerisation
Closed Co-Extrusion
Method
Centrifugal Method

18. FABRICATION OF STEP INDEX
POFs
A step Indexed plastic optical fiber has a simple
structure of a concentric core aand cladding.
Consequently rather simple fabrication techniques can
be applied for its fabrication, these techniques are
described as under.
1. Continous Extrusion Technique.
2. Preform Method

19. CONTINOUS EXTRUSION
METHOD
The polymer which becomes
the core of SI- POF is then
fed into a extruder by a gear
pump. The extruder is
capable of devolatalisation,
which removes monomer
residue and returns them to
the reactor. The core material
and the cladding material,
which are fed by separate
extruders, proceed into a
extrusion die where
concentric core - cladding
structure of an SI- POF is
formed.

20. PREFORM METHOD (SI POFs)
Method involves
two stages:
1. A cylindrical
preform 1-5 cm
in diameter and
upto 1 m in
length is made.
2. The preform is
drawn into a
fiber by heat
drawing
process.

21. FABRICATION OF GI- POFs
GI- POF has drawn considerable attention in the recent past as a high
bandwidth data transmission medium. The bandwidth of the POF is
maximized by optimizing the Distribution of Refractive Index.
Thus in manufacturing of GI- POF, the obtainable bandwidth of a
GI POF is directly related to the ability to control profile. To date
several methods have been proposed to for the manufacture of GI
POF. These methods are described in the upcoming sections.
 Photo copolymrization.
 Swollen Gel Polymerization.
 Closed Extrusion Method.
 Centrifugal Method.

22. PHOTO COPOLYMERISATION
(GI POFs)
• A 2.9 mm diameter glass tube
was was filled with a monomer
mixture methyl methacrylate and
vinyl benzoate and an initiator
benzoyl per oxide. the glass tube
reactor was then positioned
vertically in a constant
temperature chamber and rotated
about its vertical axis
• It is irradiated by UV. the UV
radiation was applied locally by
using a shade while the UV lamp
transversed from the bottom of
the tubular reactor to the top at a
constant speed.

23. SWOLLEN GEL
COPOLYMERIZATION (GI POFs)
A two stage process:
1. The monomer mixture is filled in the polymer tube to form gel at a lower
temperature to form a gel without significant copolymerization.
2. The temperature is raised to polymerization temperature to polymerize the
monomer, hence a rod is formed, which can be drawn into graded index
polymer optical fibre.

24. CLOSED CO EXTRUSION
METHOD (GI POFs)
• Versatile technology for making GI
POFs.
•The figure shows a schematic
diagram of the a N layer internal
diffusion and surface evaporation co
extrusion process.
•The tanks labeled 1- N are filled
with polymer melts.
•They are arranged so that when fed
to the concentric die the materials are
in decreasing order of the refractive
index of the polymers.
•It is thed passed through a hardening
zone H and is then receives by rolls.

25. CENTRIFUGAL METHOD
(GI POFs)
The centrifugal method is regarded as a potential method for the
preparation of the GI polymer rods because of the ability to
form large diameter GI rods. The figure here shows the
schematic representation of the preparation of the GI polymeric
rods by centrifugal method. Many aspects of this method are still
being studied

26. POLYMER OPTICAL FIBER
GRATINGS
Fiber Bragg Grating is
characterised by a periodic
index change induced by
ultraviolet irradiation in the
core along the fiber. Light
propagating along the fiber
grating is periodically and
partially reflected in
accordance with the pattern
of the index change. When
theses reflections are in
phase, they can produce an
enhanced near 100%
reflection.

27. FABRICATION OF POF
GRATINGS
 ABLATION: This involves melting and burning the polymer
surface.
 CHAIN SCISSION: This involves breaking the polymer chains,
thus decreasing the chain density, which in turns reduces the
refractive index.
 CROSS LINKING: This involves inducing free radicals and then
giving rise to the combination of polymer chains. This has the effect
of increasing the density of chains, thus increasing the refractive
index of the polymer.
 PHOTO POLYMERISATION: The incident light generates free
radicals , thus causing the polymerization of unreacted monomer
within the polymer. As a result, the polymerization density increases
and the refractive index increases accordingly.

28. POF PASSIVE DEVICES
OPTICAL COUPLERS
In applications of POF such as
signalising, lighting, and decoration
systems, where it is necessary to
distribute or redirect incoming light
to other outgoing fibers, to split or
combine optical signals into two or
more fibers
FILTERS
Large core optical fiber have as in
polymer optical fiber have a large
number of propogation node
which can cause to noise in
communication hence filters are
employed. Obtained by wrapping a
pof in a small diameter cylinder.

29. TAPERS
For some applications such as light
emitting diode to POF coupling,
step index to GI POF coupling,
collimation , it is necessary to
reduce the fiber diameter.
LENSES
For many applications it is
necessary to use a Fiber
Integrated Lens, which is a device
that fits the fiber size and is used
to focus or collimate the the fiber
output light beam

30. FUTURE ASPECTS
 Polymer Optic
Fibers Polymer
optical fibers
offer many
benefits when
compared to
other data
communication
solutions such as
copper cables,
wireless
communication
systems, and
glass fiber.

31. •In comparison with glass optical fibers,
polymer optical fibers provide an easy and less
expensive processing of optical signals, and are
more flexible for plug interconnections .
• The use of polymer optical fibers as the
transmission media for aircrafts is presently
under research by different Research and
Development groups due to its benefits. The
German Aerospace Center have concluded that
“the use of Polymer Optical Fibers multimedia
fibers appears to be possible for future aircraft
applications.
•In the future, polymer optical fibers will likely
displace copper cables for the last mile
connection from the telecommunication
company’s last distribution box and the served
end consumer.

32. REFERENCES
 Hari Singh Nalwa.(Ed.).(2004). Polymer Optical
Fibers. American Scientific Publishers.
• Chang-Won Park. Fabrication Techniques for Plastic Optical Fibers. USA
• Wen-Chang Chen,
Jui-Hsiang Liu, Yung Chang, Ming-Hsin Wei, and Hong-Wen Su. Gradient-
Index Polymer Optical Fibers: Analysis of Fabrication Techniques. Taiwan.
• Giok-Djan Khoe, Henrie van den Boom,
and Idelfonso Tafur Monroy. High Capacity Transmission System. The
Netherlands
• G. D. Peng and P. L. Chu. Polymer Optical Fiber Gratings, Australia.
• Liliana R. Kawase. Plastic Optical Fiber Passive Device. Brazil.
 An overview on fabrication method for polymer optical fibers.
Christian -Alexander Bunge. www.academia.edu
 Plastic optical fiber Vs Glass optical Fiber. Retrieved from
www.fiberopticsshare.com.
 Polymer optical fiber (n.d). Retrieved February 5, 2016, from
en.wikipedia.org/wiki/Plastic_optical_fiber.