Optical Fiber AUTO3160 - Optics and Spectroscopy Spring 2012
Miguel Angel Chourio Masters degree in Telecommunication
Engineering University of Vaasa, Finland Slide 2 What is a Optical
Fiber Single Mode Optical Fiber Multimode Optical Fiber Single mode
Vs. Multimode Fiber Snews Law - Total Internal Reflection How is
glass optical Fiber made Applications Conclusions References INDEX
Slide 3 Optical Fiber Optical Fiber uses glass to guide the light
impulses from source to destination. Optical Fiber provides a very
large bandwidth data rates. Based on its requirements and needs,
Networks communication are implemented as oCopper oOptical Fiber
oWireless (Signal are propagated over the air) Slide 4 Glass Fiber
Structure The core vary its dimensions either the fiber is single
or multimode. Light enter into the core and its cladding along the
fiber The Cladding surronds or cover the core and is designed to
prevent light loss from the fiber. Since the light can only travel
in one direction over the optical cable, two fibers are required to
support full duplex operations Slide 5 Ray Light explanation
Typically, the core size on Multiple Fiber are large enough so
that, multiple light ray can enter to the core at different angles
along the fiber. Multimode fiber employ Light Emitting Diodes
(LEDs) with its proper angles to represent the transmitted data as
bits along the media. Due the light enters the fiber at different
angles, it takes different amount of time to travel down the fiber,
and it may become confuse at the receiver side. This effect known
as modal dispersion, limit the length of multimode fiber segments.
Slide 6 Ray Light explanation In Single Fiber, the core is so tiny
that only one light ray which is perpendicular to the cable may be
propagate along. Single Fiber employs a single Ray of Light as
source generator to propagate the signals, because the laser is
uni- directional and travels along the center of the fiber. Slide 7
Single mode vs. Multimode Fibers Single-ModeMultimode Small core
Less dispersion Carry a single ray of light, usually generated from
a laser. Employ for long distance applications (100Km) Uses as
Backbone and distances of several thousands meters. Larger core
than single mode cable. Allows greater dispersion and therefore,
loss of signal. Used for shorter distance application, but shorter
than single-mode (up to 2Km) It uses LED source that generates
differtes angles along cable. Often uses in LANs or small distances
such as campus networks. Slide 8 Waveguide calculation of Fiber
Mode Here is fiber mode calculation based on Waveguide Calculation
by Fiber Optics for Sale Company (USA) V number determines the
numbers of guided modes. When V number is smaller than 2.405 only
one mode can be guided by the fiber, this is called single mode
fiber. When V Numer is larger than 2.405 severals modes can be
guided by the fiber. As higer V number as larger number of modes,
this is called Multimode Fiber Slide 9 Multimode Fibers is more
complex The multimode fiber keeps the same structure as single mode
unlike the sieze of the core glass is bigger. Refractive index
profile in multimode fibers The x (axes )shows fiber raduis The y
(axes ) shows refractive index The core usually has a refractive
index n1 = 1.48 The cladding has a refractive index n2 = 1.06 This
is called Step-index fiber Slide 10 Snews Law - Total Internal
Reflection Snews Law describe the relation between the angles of
incidents and refractions. When the Light Ray pass from a higher
index material to a lower index material, light refraction occurs.
When light incidents at interface between the core and the cladding
has differents angles some power are reflacting back and some power
enter into the cladding As the angle is increases larger than the
target no more light enter into the Cladding layer and all the
light reflect back into the core. This is called Total Internal
Reflection. Core Cladding Slide 11 Optical Fiber manufacturer
Generally it consists on 2 steps by Glass Fiber preform Fiber
Manufacturing Process 1st Step a preform is made and it has quite
exactly the same proportion core as the cladding material. 2nd Step
the preform pass through a monitor to deploy the final fiber into a
drum to be storage and distributed. Slide 12 Special fiber drawing
tower Optical Implementation Technology offers by Yangtze Optical
Fibre and Cable Company Ltd. (YOFC) a Chinese company established
in May 1988. Reference
http://en.yofc.com.cn/jjfa/&FrontComContent_list01-1293619915029ContId=279b108f-7f52-
4951-a347-9afb3bec0dcb&comContentId=279b108f-7f52-4951-a347-
9afb3bec0dcb&comp_stats=comp-FrontComContent_list01-1293619915029.html
http://en.yofc.com.cn/jjfa/&FrontComContent_list01-1293619915029ContId=279b108f-7f52-
4951-a347-9afb3bec0dcb&comContentId=279b108f-7f52-4951-a347-
9afb3bec0dcb&comp_stats=comp-FrontComContent_list01-1293619915029.html
Slide 13 Nowadays, Optical Fibers connects the world under the sea
and over the land Basically all digital communications travels via
fiber. A single fiber can carry more communications than the
biggest copper cable. Optical Fibers Applications Slide 14
Telecommunications | Internet | Fiber at Home Video Streaming |
Data Centers | Computer Networks Video and Audio Military |
Governments | Airports |Hospital Intelligent | Public
transportations Everywhere Slide 15 Conclusion Optical Fiber =
Optical + Fiber At Speed of Light Single Mode Fiber provides higher
data rates speed and more distance than Single Mode Single Mode
uses a single Ray of Light while Multimode Fiber employ Light
Emitting Diodes (LEDs) to propagate the signal. At present, the
fiber application might be infinite, however a deep analysis and
design is recommended before implement a network. Slide 16
Reference [1] Yangtze Optical Fibre and Cable Company Ltd. (YOFC)
http://en.yofc.com.cn/jjfa/&FrontComContent_list01-1293619915029ContId=279b108f-7f52-
4951-a347-9afb3bec0dcb&comContentId=279b108f-7f52-4951-a347-
9afb3bec0dcb&comp_stats=comp-FrontComContent_list01-1293619915029.html
[2] CISCO Networking Academy Program CCNA 1 and 2 book, 3rd
Edition, Indianapolis CISCO press, 2003. [3] About Optical Fiber,
link:
http://en.wikipedia.org/wiki/Optical_fiberhttp://en.wikipedia.org/wiki/Optical_fiber
[4] Eugene Hecht Optics, International Edition, Pearson Education
Slide 17 Thank you Kiitos Tack
