fiber optics in textile

FIBER OPTICS IN TEXTILE
Rsch. Assist. Kami Emirhan
Yeditepe University,
Faculty of Fine Arts,
Department of Fashion and
Textile Design, Turkey
[email protected]
1.Fiber Optics
Fiber optics are long, thin strands of very pure glass
about the diameter of a human hair. They are
arranged in bundles called optical cables and used to
transmit light signals over long distances.
Multi-mode fibers have larger cores (about 2.5 x 103 inches or 62.5 microns in diameter) and transmit
infrared light (wavelength = 850 to 1,300 nm) from
light-emitting diodes (LEDs).
Some optical fibers can be made from plastic. These
fibers have a large core (0.04 inches or 1 mm
diameter) and transmit visible red light (wavelength =
650 nm) from LEDs.
1.1.The Relationship between Light and Fiber Optics
Suppose you want to shine a flashlight beam down a
long, straight hallway. Just point the beam straight
down the hallway and light travels in straight lines, so
it is no problem. If the hallway has a bend in it, you
can place a mirror at the bend to reflect the light
beam around the corner. And if the hallway is very
winding with multiple bends you may line the walls
with mirrors and angle the beam so that it bounces
from side-to-side all along the hallway.
This is exactly what happens in an optical fiber.
Scheme 1 Parts of a single optical fiber
- Core - Thin glass center of the fiber where the
light travels
- Cladding - Outer optical material surrounding the
core that reflects the light back into the core
- Buffer coating - Plastic coating that protects the
fiber from damage and moisture
There are two types of optical fibers:
- Single-mode fibers
- Multi-mode fibers
Single-mode fibers have small cores (about 3.5 x 104 inches or 9 microns in diameter) and transmit
infrared laser light (wavelength = 1,300 to 1,550
nanometers).
Scheme 2 total internal reflection in an optical fiber
The light in a fiber-optic cable travels through the
core (hallway) by constantly bouncing from the
cladding (mirror-lined walls), a principle called total
internal reflection (Scheme 2). 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 on the purity of the glass and the
wavelength of the transmitted light.
1.2. A Fiber-Optic Relay System
To understand how optical fibers are used in
communication systems, let's look at an example
from World War II. Suppose that two naval ships in a
fleet need to communicate with each other while
maintaining radio silence. One ship pulls up
alongside the other. The captain of one ship sends a
message to a sailor on deck. The sailor translates the
message into Morse code and uses a signal light to
send the message to the other ship. A sailor on the
deck of the other ship sees the Morse code message,
decodes it into English and sends the message up to
the captain.
Now, imagine doing this when the ships are on either
side of the ocean separated by thousands of miles
and you have a fiber-optic communication system in
place between the two ships.
Fiber-optic relay systems consist of the following:
- Transmitter - Produces and encodes the light
signals
- Optical fiber - Conducts the light signals over a
distance
- Optical regenerator - May be necessary to boost
the light signal (for long distances)
- Optical receiver - Receives and decodes the light
signals
to the other user's computer, TV or telephone
(receiving ship's captain). The receiver uses a
photocell or photodiode to detect the light.
2. Fiber Optics In Textile
2.1. Smart Shirt
In October 1996, A project called “Georgia Tech
Wearable Motherboard” (Smart Shirt) was initially
funded by the U.S. Navy and in 2000, The Georgia
Tech Research Corporation licensed the technology
to New York-based SensaTex Inc. to manufacture
and market the Smart Shirt. Dr. Sundaresan
Jayaraman, who is a professor at the School of
Textile & Fiber Engineering Georgia Institute of
Technology, is also the principal investigator at this
project.
According to Jayaraman, Smart Shirt is a computer tshirt woven with fiber optics and electrically
conductive thread that can monitor the health of
soldiers, rescuers, the elderly and others who are
medically vulnerable. The main advantage of Smart
Shirt is that it provides a very systematic way of
monitoring the vital signs of humans in an
undisturbing manner. To use this new technology;
first sensors are attached to the body, then the shirt
is pulled on and sensors are attached to the shirt.
Transmitter
The transmitter is like the sailor on the deck of the
sending ship. It receives and directs the optical
device to turn the light "on" and "off" in the correct
sequence, thereby generating a light signal.
Optical Regenerator
Some signal loss occurs when the light is transmitted
through the fiber, especially over long distances
(more than a half mile, or about 1 km) such as with
undersea cables. Therefore, one or more optical
regenerators are spliced along the cable to boost the
degraded light signals.
Optical Receiver
The optical receiver is like the sailor on the deck of
the receiving ship. It takes the incoming digital light
signals, decodes them and sends the electrical signal
Figure 1 The fabric being
woven
Figure 2 Prof. Dr. Sundaresan Jayaraman wearing the
Smart Shirt
Figure 2 shows that Smart Shirt is “armed” and ready
to detect what is going on in a soldier’s body at a
battlefield. Shirt itself is so customizable that sensors
to detect any required information, such as; bullet
wounds, temperature, heart rate and respiration rate,
oxygen levels or hazardous gas levels (which
indicates that Smart Shirt can also be used by fire
department or police department) can be added if
necessary. This flexible data bus integrated into the
structure, transmits the signals to the army
headquarters or in civilian case to the fire station or
to the police station giving information about the
health status of the person who wears it.
Georgia Tech Wearable Motherboard can also be
used on patients that are continuously need to be
monitored (e.g., patients discharged after major
surgeries, patients those are suffering from manic
depression) and this reveals the possibility of
telemedicine. Likewise, continuous monitoring of
astronauts in space, of athletes during practice
sessions and in competition are all extremely
important.
on luminous diodes. A special abrasion process for
the fibers at the surface of the fabric associated to a
specific fabric weave developed by the France
Telecom laboratories made it possible to create the
first bitmap screen matrix on a flexible textile base.
Figure 3 Clothing with a flexible fiber-optics screen and
remote-control
Smart Shirt, which can be laundered without any
damage to the sensors themselves, is no doubt one
of the 21st century’s best inventions and in 2002 it
took its place among the Smithsonian Institution’s
collection of important items in the history of textile in
Washington, D.C.
2.2. Flexible Screen
France Telecom R&D, announced in the press
release May 03, 2002 that, it has designed a
prototype for a flexible screen made of woven optical
fibers capable of downloading and displaying static or
animated graphics such as; logos, texts, patterns,
scanned images etc. By this innovation we
understand that, clothes can now act as a graphical
communication
interface,
displaying
visual
information in real time and offering access to all
telecom services (internet, video, e-commerce and
3G mobiles).
This unique display technology is based on the
association of fabric containing optical fibers and an
electronic control system that controls lighting based
Figure 4 Backpack with a flexible fiber-optics screen and
remote-control
Figure 5 Flexible Screen
on a scarf
Figure 6 Flexible Screen
on clothing
The fabric functions like a screen on which all sorts of
visual information can be downloaded through a
wireless link (by using radio waves or Bluetooth
Technology) via the internet from an office computer
or a mobile, or even a dedicated internet site. A
flexible remote-control in the garment makes it
possible to call up the visuals stored in the clothing’s
memory and to generate several related special
effects.
2.3. Luminex
After numerous attempts and experiments, it has
finally been possible to integrate a luminous fibre into
a fabric, giving its own brilliance. Luminex is a new
fabric that can emit its own light.
It’s the result of a close collaboration between a
highly technological electronics company like CAEN
spa, which is in fact the world’s leading company in
the planning and production of electronic equipment
for use in Nuclear physics experiments, and two
companies operating in textiles sector FIT spa in
Prato and the Swiss company STABIO sa.
In Luminex, together with optic bright and/or
sparkling fibers, natural and synthetic fibers can be
used. Natural and/or synthetic fibers may be of any
color. Fibers transmitting light are uncolored, they
take the color of the bright source which is connected
to them. Luminex can be supplied directly by 200/110
Volt using a smaller transformer (i.e.: loading for
mobile phone batteries) or by a mini-battery which
can be re-loaded.
Figure 7 Flexible Screen on backpack
Previewed at Avantex 2002, the international trade
show for garment textile innovation, this prototype of
a flexible screen, was awarded the prize for
Research and Development Innovation and definitely
it will be one of the most important usage patterns for
the advertising industry.
Figure 9 A closer look at Luminex
The first application is easily suitable for curtains,
panels, and fixed structures, while the second for
wearing clothes or for all mobile things. The battery is
inserted in the more practical available housing,
according to the manufacturing. For example, into a
pair of jeans the housing is usually a small pocket on
the right side of the trouser.
Figure 8 A closer look at the Flexible Screen
Figure 12 LUMINEX used to cover chair
Figure 10 Bag made of Luminex by United Colors of
Benetton
Luminex has already manufactured and displayed
several items to be sold on its internet site. Among
them are, cushions, bras, shirts, bags etc.
Figure 13 LUMINEX on several decorative and functional
objects
Figure 11 LUMINEX used as a tablecloth
In Figure 11, 12, 13, it is clearly visible that LUMINEX
will play a major role in the interior decoration sector.
Figure 14 A closer look at Luminex
3. Summary
Textile has always been one of the indispensables of
our lives. The concept of design was always there.
Then technology was invovled and eventually came
the mass producton. With the inclusion of synthetic
raw materilas to the textile world, vision of design
expanded beyond dreams and now Fiber Optics are
intruduced to us.
With Fiber Optics, engineers and designers have
come up with quite creative ideas of modifying our
daily lives by integrating it into a woven fabric. It’s
doubtlessly fascinating that, usage of this facility
revealed the possibility of telemedicine, which
suggests; monitoring and treatment of humans those
in post-operative recovery, geriatric patients,
mentally ill patients, children susceptible to sudden
infant death syndrome and individuals prone to
allergic reactions, and these are just a few forseen
examples. Army, Police Departments and Fire
Departmens will also be capable of monitoring their
staff during a healthcare situation.
Another major concequence of this new invention is
of course its commercial side. Wouldn’t it be great if
you possessed an armchair that glows at night and
you could change its color within seconds, or a table
cloth, a cushion, a curtain, a panel, a rug or even an
umbrella with the same qualifications? Maybe you
would like to wear garments or use a backpack of
that kind on which you can display constantly
changing colors and images. And these, brings to
mind the fact that, advertisement and entertainment
sectors will also be one of the most to benefit from
this innovation.
In conclusion, as long as the interactivity between
design, technology and manufactuirng develops
gradually by the desire to design, which is the major
fact that pushes technology onwards, we can be sure
that such breakthroughs will not only expedite our
lives but also play a vital role on our existence.
Bibliography
Schemes 1,2
www.howstuffworks.com
Fig. 1,2
www.gtwm.gatech.edu
Fig. 3,4,5,6,7,8
www.francetelecom.fr
Fig. 9,10,11,12,13,14
www.luminex.it