View
211
Download
7
Category
Preview:
DESCRIPTION
Final Report
Citation preview
E – Paper
1. INTRODUCTION
Todays electronic displays have ever more evolved to be more lightweight, efficient
and clear. Yet the importance of the paper has not diminished. We still prefer it to others for a
variety of reasons including its readability, high contrast, convenient handling, minimum
power requirement cost and strain less reading it offers. At the same time, an electronic
display offers us a paperless environment and relieves us from carrying loads of paper for
referring to information when required.
Electronic ink is a pioneering invention that combines all the desired features of a
modern electronic display and the sheer convenience and physical versatility of sheet of
paper. E-paper or electronic paper is sometimes called radio paper or smart paper. Paper
would be perfect except for one obvious thing: printed words can’t change. The effort is to
create a dynamic high-resolution electronic display that’s thin and flexible enough to become
the next generation of paper.
The technology has been identified and develop ed is well under way. Within five
years, it is envisioned electronic books that can display volumes of information as easily as
flipping a page and permanent newspapers that update themselves daily via wireless
broadcast. They deliver the readability of paper under virtually any condition, without back
lighting. And electronic ink displays are persistent without power, drawing current only when
they change, which means batteries can be smaller and last longer.
1
E – Paper
1.1 History
Electronic paper was first developed in the 1970s by Nick Sheridan at Xerox’s Palo
Alto Research center. The first electronic paper, called Gyricon, consisted of tiny, statically
charged balls that were black on one side and white on the other. The "text" of the paper was
altered by the presence of an electric field, which turned the balls up or down. In the 1990s
another type of electronic paper was invented by Joseph Jacobson, who later co- founded the
corporation E Ink which formed a partnership with Philips Components two years later to
develop and market the technology
2
E – Paper
2. TECHNOLOGY USED
2.1 Gyricon
Electronic paper was first developed in the 1970s by Nick Sheridon at Xerox's Palo
Alto Research Center. The first electronic paper, called Gyricon, consisted of polyethylene
spheres between 75 and 106 micrometers across. Each sphere is a Janus particle composed of
negatively charged black plastic on one side and positively charged white plastic on the
other(each bead is thus a dipole). The spheres are embedded in a transparent silicone sheet,
with each sphere suspended in a bubble of oil so that they can rotate freely. The polarity of
the voltage applied to each pair of electrodes then determines whether the white or black side
is face-up, thus giving the pixel a white or black appearance. At the FPD 2008 exhibition,
Japanese company Soken has demonstrated a wall with electronic wall-paper using this
technology
3
E – Paper
2.2 Electrophoretic
An electrophoretic display forms visible images by rearranging charged pigment particles
using an applied electric field.
In the simplest implementation of an electrophoretic display, titanium dioxide particles
approximately one micrometer in diameter are dispersed in a hydrocarbon oil. A dark-colored
dye is also added to the oil, along with surfactants and charging agents that cause the particles
to take on an electric charge. This mixture is placed between two parallel, conductive plates
separated by a gap of 10 to 100 micrometers. When a voltage is applied across the two plates,
the particles will migrate electrophoretic ally to the plate bearing the opposite charge from
that on the particles.
4
E – Paper
When the particles are located at the front (viewing) side of the display, it appears
white, because light is scattered back to the viewer by the high- index titanium particles.
When the particles are located at the rear side of the display, it appears dark, because the
incident light is absorbed by the colored dye. If the rear electrode is divided into a number of
small picture elements (pixels), then an image can be formed by applying the appropriate
voltage to each region of the display to create a pattern of reflecting and absorbing regions.
Electrophoretic displays are considered prime examples of the electronic paper
category, because of their paper- like appearance and low power consumption.
Electrophoretic displays can be manufactured using the Electronics on Plastic by Laser
Release (EPLaR) process developed by Philips Research to enable existing AM-LCD (Active
matrix liquid crystal display) manufacturing plants to create flexible plastic displays.
5
E – Paper
2.2.1 Electronics on Plastic by Laser Release (EPLaR)
Electronics on Plastic by Laser Release (EPLaR) is a method for manufacturing
flexible electrophoretic display using conventional AM-LCD manufacturing equipment
avoiding the need to build new factories. The technology can also be used to manufacture
flexible OLED (Organic LED) displays using standard OLED fabrication facilities.
The technology was developed by Philips Research and uses standard display glass as
used in TFT-LCD processing plants. It is coated with a layer of polyimide using a standard
spin-coating procedure used in the production of AM-LCD displays. This polyamide coating
can now have a regular TFT matrix formed on top of it in a standard TFT processing plant to
form the plastic display, which can then be removed using a laser to finish the display and the
glass reused thus lowering the total cost of manufacture.
6
E – Paper
2.2.2 Development in Electrophoretic Display:
In the 1990s another type of electronic paper was invented by Joseph Jacobson, who later co-
founded the E Ink Corporation which formed a partnership with Philips Components two
years later to develop and market the technology. In 2005, Philips sold the electronic paper
business as well as its related patents to Prime View International. This used tiny
microcapsules filled with electrically charged white particles suspended in colored oil. In
early versions, the underlying circuitry controlled whether the white particles were at the top
of the capsule (so it looked white to the viewer) or at the bottom of the capsule (so the viewer
saw the color of the oil). This was essentially a reintroduction of the wellknown
electrophoretic display technology, but the use of microcapsules allowed the display to be
used on flexible plastic sheets instead of glass.
One early version of electronic paper consists of a sheet of very small transparent
capsules, each about 40 micrometers across. Each capsule contains an oily solution
containing black dye (the electronic ink), with numerous white titanium dioxide particles
suspended within.
The particles are slightly negatively charged, and each one is naturally white. The
microcapsules are held in a layer of liquid polymer, sandwiched between two arrays of
electrodes, the upper of which is made transparent.
7
E – Paper
The two arrays are aligned so that the sheet is divided into pixels, which each pixel
corresponding to a pair of electrodes situated either side of the sheet. The sheet is laminated
with transparent plastic for protection, resulting in an overall thickness of 80 micrometers, or
twice that of ordinary paper.
The network of electrodes is connected to display circuitry, which turns the electronic
ink 'on' and 'off' at specific pixels by applying a voltage to specific pairs of electrodes.
Applying a negative charge to the surface electrode repels the particles to the bottom of local
capsules, forcing the black dye to the surface and giving the pixel a black appearance.
Reversing the voltage has the opposite effect - the particles are forced from the surface,
giving the pixel a white appearance. A more recent incarnation of this concept requires only
one layer of electrodes beneath the microcapsules.
8
E – Paper
2.3 Electrowetting
Electro-wetting display (EWD) is based on controlling the shape of a confined water/oil
interface by an applied voltage. With no voltage applied, the (coloured) oil forms a flat film
between the water and a hydrophobic (water-repellent), insulating coating of an electrode,
resulting in a colored pixel.
When a voltage is applied between the electrode and the water, the interfacial tension
between the water and the coating changes. As a result the stacked state is no longer stable,
causing the water to move the oil aside.
This results in a partly transparent pixel, or, in case a reflective white surface is used
under the switchable element, a white pixel. Because of the small size of the pixel, the user
only experiences the average reflection, which means that a high-brightness, high-contrast
switchable element is obtained, which forms the basis of the reflective display.
9
E – Paper
Displays based on electro-wetting have several attractive features. The switching
between white and colored reflection is fast enough to display video content.
It is a low-power and low-voltage technology, and displays based on the effect can be
made flat and thin. The reflectivity and contrast are better or equal to those of other reflective
display types and are approaching those of paper. In addition, the technology offers a unique
path toward high-brightness full-color displays, leading to displays that are four times
brighter than reflective LCDs and twice as bright as other emerging technologies.
Instead of using red, green and blue (RGB) filters or alternating segments of the three
primary colors, which effectively result in only one third of the display reflecting light in the
desired color, electro-wetting allows for a system in which one sub-pixel is able to switch two
different colors independently. This results in the availability of two thirds of the display area
to reflect light in any desired color. This is achieved by building up a pixel with a stack of
two independently controllable colored oil films plus a color filter.
10
E – Paper
2.4 Electrofluidic
Electrofluidic displays are a variation of an electro wetting display. Electro fluidic displays
place an aqueous pigment dispersion inside a tiny reservoir. The reservoir comprises <5-10%
of the viewable pixel area and therefore the pigment is substantially hidden from view.
Voltage is used to electromechanically pull the pigment out of the reservoir and spread it as a
film directly behind the viewing substrate. As a result, the display takes on color and
brightness similar to that of conventional pigments printed on paper. When voltage is
removed liquid surface tension causes the pigment dispersion to rapidly recoil into the
reservoir. As reported in the May 2009 Issue of Nature Photonics, the technology can
potentially provide >85% white state reflectance for electronic paper.
11
E – Paper
3. KEY BENEFITS
E-Paper has numerous benefits. The reader does not need to get used to a new format-
reading an E-Paper equals reading a printed newspaper. However, E-Paper guarantees in
dependency regarding room and time. E-Paper can be read everywhere in the world, at every
hour, and since digital editions can also be received on PDAs and smart phones, mobility is
almost limitless. Additionally, E-Paper saves resources. On the one hand, paper and space are
saved - because E-Paper does not pile up anywhere - on the other hand, valuable time is
saved. Since the complete pages are displayed on the PC monitor, one instantly gets an
overview over all headlines and thus gets to the relevant articles a lot faster Unlike
conventional LCDs and other kinds of reflective displays, an electronic ink display is
exceptionally bright and is ready viewable under both bright and dim lighting conditions. To
be more assertive we could compare electronic ink display with the latest liquid crystal
displays.
12
E – Paper
Table 3.1: Comparison of E- ink & LCD
3.1 Paper-like Readability
Paper is easily readable over wide variations in lighting conditions and viewing angle .E Inks
electronic ink technology approaches printed paper in performance by incorporating the same
coloring pigments often used to make paper white and ink black.
When reading text, both reflectance and contrast are important factors in determining
the readability of a display. In fact, the contrast of E Ink is nearly twice that of printed
newspaper. As can be seen from its high reflectance and contrast the E Ink display is much
more readable than LCD.
The bright paper-white background of electronic ink eliminates the need for a
backlight is most conditions.
13
E – Paper
3.2 Ultra-Low Power Consumption
Electronic ink displays offer greatly reduced power consumption. Lower power
consumption translates to longer battery life, and perhaps more importantly, the ability to use
smaller batteries in electronic ink devices- reducing device weight and cost. The reason for
the reduced power consumption offered by electronic ink displays is two- fold: (1) they are
completely reflective requiring no backlight and (2) they are inherently bi-stable for extended
periods of time. Once an image is written on an electronic ink display, it will be retained
without additional power input until the next image is written. Hence the power consumption
of an electronic ink display will ultimately depend upon the frequency at which the displayed
image is changed. However, in both cases, a reduction in power consumption by several
orders of magnitude can be achieved by using electronic ink with its bi-stable imaging.
3.3 Thin, Light Form Factor
An electronic ink display module is thinner, lighter weight, and more robust than
conventional LCDs. These benefits are especially important in smart handheld applications
where portability is paramount. First generation, electronic ink displays will be b ut by
laminating electronic ink to a conventional glass TFT substrate In addition, no polarizes are
required for electronic ink displays. The resulting electronic ink display cell is also about half
that of a typical LCD cell. Elimination of the glass top sheet means that displays made within
electronic ink display module should be inherently more robust.
14
E – Paper
3.4 The Ultimate Mobile Display Solution
Paper-like viewing characteristics and appearance, combined with ultra- low power
consumption and thin light form factors, make E inks electronic ink display material the ideal
technology solution for information intensive, handheld devices such as PDAs, mobile
phones and electronic readers; or any applications requiring a high degree of displayegibility.
15
E – Paper
3.5 Twistable
Electronic Paper is made using soft plastic containing small particles and fluid. As there is no
hard material, Electronic Paper is highly flexible and it is able to be twisted orb ended into
different curvatures. The Electronic Paper can be applied to different shapes of products,
without being limited to being bonded to flat display panels. The end product becomes more
imaginative in shape and style.
16
E – Paper
3.6 Simple Manufacturing Process
The manufacturing process is carried out using a roll- to-roll method, similar to printing
paper, by injecting dielectric fluid and charged particles into the layer of capsules, and then
sealing the top layer. The production is performed continuously at high speed. The Electronic
Paper can be produced in a large form and then cut into any desired size and shape for
different application requirements.
17
E – Paper
4. HIGHLIGHTS OF ELECTRONIC INK
Electronic ink moves information display to a new dynamic level, with dramatic benefits over
traditional media.
Superior Look - Because its made from the same basic materials as regular ink and
paper, electronic ink retains the superior viewing characteristics of paper, including
high contrast, wide viewing angle, and bright paper-white background.
Versatile - Electronic ink can be printed on almost any surface, from plastic to metal
to paper. And it can be coated over large areas cheaply.
Low Power - Electronic ink is a real power miser. It displays an image even when the
power is turned off and its even legible in low light reducing the need for a backlight.
This can significantly extend battery life for portable devices.
18
E – Paper
Scalable - E Inks electronic ink process is highly scalable, which makes it
competitive against todays older technologies
19
E – Paper
5. DISADVANTAGES
Electronic paper technologies have a very low refresh rate comparing with other low-
power display technologies, such as LCD. This prevents producers from implementing
sophisticated interactive applications (using fast moving menus, mouse pointers or scroll
ing) like those which are possible on handheld computers. An example of this limitation
is that document cannot be smoothly zoomed without either extreme blurring during the
transition or a very slow zoom.
Another limitation is that an imprint of an image may be visible after refreshing parts
of the screen. Those imprints are known as "ghost images", and the effect is known as
“ghosting". This effect is reminiscent of screen burn- in but, unlike it, is solved after the
screen is refreshed several times. Turning every pixel white, then black, then white, helps
normalize the contrast of the pixels. This is why several devices with this technology
"flash “the entire screen white and black when loading a new image, in order to prevent
ghosting from happening.
20
E – Paper
6. APPLICATIONS
Electronic Paper behaves similarly to conventional paper, a lowing high readability under
low or high light conditions, and being thin and lightweight and fully pliable. In addition,
Electronic Paper has the advantage of allowing the content to be changed easily at any
time via the Electronic Paper driver IC. Electronic Paper will provide a viable substitute
to paper in certain areas. Some examples of Electronic Paper applications are described
below.
6.1 Electronic Shelf Label
In a large department store or supermarket, there are many price tag labels on the shelves
indicating product price. Whenever there is a change of price information, it is very
tedious to change the price tags individually. By replacing the paper price tag with
Electronic Paper, the price information can be easily updated once the Electronic Paper
price tags are connected via a wireless network.
21
E – Paper
The Electronic Paper price tag requires no battery power to maintain display and prices
can be updated using the energy from the RF wave to change the image content.
6.2 Electronic Watch and Clock
Watch and clock designs can become more imaginative using Electronic Paper.
For example, a watch using Electronic Paper will allow time and image to be displayed
on the wrist strap of the watch.
22
E – Paper
6.3 e-Books
In 2004 Sony released Librium EBR-1000EP in Japan, the first e-book reader with an
electronic paper display. In November 2006, the iRex iLiad was ready for the consumer
market. In November 2009 Barnes and Noble launched the Barnes & Noble Nook, based
on the Android operating system.
In late 2007, Amazon began producing and marketing the Amazon Kindle, an e-book
reader with an e-paper display.
23
E – Paper
Fig - 6.3: Sony E- book reader
24
E – Paper
6.4 Smart Card Display
Today, many credit cards contain a smart card to store information such as
accumulated credit and money expenses etc. Since Electronic Paper has the advantage of
lower power consumption and is as flexible as the card, it offers a good solution to displaying
this type of information on the card.
25
E – Paper
6.5 Newspapers
In February 2006, the Flemish daily De Tied distributed an electronic version of the
paper to select subscribers in a limited marketing study, using a pre-release version of the ire
Iliad. This was the first recorded application of electronic ink to newspaper publishing. In
September 2007, the French daily Les Echo’s announced the official launch of an electronic
version of the paper on a subscription basis.
Since January 2008, the Dutch daily NRC Handelsblad is distributed for the
iRexiLiad reader
Fig-6.4: Electronic newspaper
26
E – Paper
6.6 Other Products
E- Ink unveiled its first product using electronic ink- immediate large-area displays- in1999.
These large signs draw only 0.1 watts of power, which means that the same power required
running a single 100-watt light bulb, could power 1,000 immediate signs. E Ink said that in
electronic devices, electronic ink would use 50 to 100 times power than liquid crystal
displays because electronic ink only needs power when changing its display. Electronic ink
can be printed on any surface, including walls, billboards, product labels and T-shirts.
Homeowners could soon be able to instantly change their digital wallpaper by sending a
signal to the electronic ink painted on their walls.
27
E – Paper
7. The Future Scenario
The Holy Grail of electronic ink technology is a digital book that can typeset itself and that
readers could leaf through just as if it were made of regular paper. Such a book could be
programmed to display the text from a literary work and once you’ve finished that tale, you
could automatically replace it by wirelessly downloading the latest book from a computer
database.
Xerox had introduced plants to insert a memory device into the spine of the book,
which would allow users to alternate between up to 10 books stored on the device. Just as
electronic ink could radically change the way we read books, it could change the way you
receive your daily newspaper.
28
E – Paper
It could very well bring an end to newspaper delivery, as we know it. Instead of
delivery people tossing the paper from their bike or out their car window, a new high- tech
breed of paper deliverers who simply press a button on their computer that would
simultaneously update thousands of electronic newspapers each morning. Sure, it would look
and feel like your old paper, but you wouldn’t have to worry about the newsprint getting
smudged on your fingers, and it would also eliminate the piles of old newspapers that need
recycling. Prior to developing digital books and newspapers E-Ink will be developing a
marketable electronic display screen for cell phones, PDAs, pagers and digital watches.
29
E – Paper
8. Conclusion
The Holy Grail of electronic ink technology is a digital book that can typeset itself and that
readers could leaf through just as if it were made of regular paper. Such a book could be
programmed to display the text from a literary work and once you've finished that tale, you
could automatically replace it by wirelessly downloading the latest book from a computer
database. Xerox had introduced plants to insert a memory device into the spine of the book,
which would allow users to alternate between up to 10 books stored on the device. Just as
electronic ink could radically change the way we read books, it could change the way you
receive your daily newspaper.
It could very well bring an end to newspaper delivery, as we know it. Instead of
delivery people tossing the paper from their bike or out their car window, a new high- tech
breed of paper deliverers who simply press a button on their computer that would
simultaneously update thousands of electronic newspapers each morning. Sure, it would look
and feel like your old paper, but you wouldn't have to worry about the newsprint getting
smudged on your fingers, and it would also eliminate the piles of old newspapers that need
recycling. Prior to developing digital books and newspapers E-Ink will be developing a
marketable electronic display screen for cell phones, PDA's, pagers and digital watches.
Electronic ink is not intended to diminish or do away with traditional displays. Instead
electronic ink will initially co-exist with traditional paper and other display technologies. In
the long run, electronic ink may have a multibillion-dollar impact on the publishing industry.
Ultimately electronic ink will permit almost any surface to become a display, bringing
information out of the confines of traditional devices and into the world around us.
30
E – Paper
REFERENCE
[1] Crowley, J. M.; Sheridon, N. K.; Romano, L. "Dipole moments of gyricon balls"
Journalof Electrostatics 2002, 55, (3-4), 247.[2] Comiskey, B.; Albert, J. D.; Yoshizawa, H.;
Jacobson, J. "An electrophoretic ink for all-printed reflective electronic displays" Nature
1998, 394, (6690), 253-255.[3] http://en.wikipedia.org/wiki/Electronic_paper.[4]
Blankenbach K, Schmoll A, Bitman A, Bartels F and Jero sch D 2008 Novel highlyreflective
and bistable electrowetting displays SID J. 16 237–44.[5] Andersson, P.; Nilsson, D.;
Svensson, P. O.; Chen, M.; Malmström, A.; Remonen, T.;Kugler, T.; Berggren, M. "Active
Matrix Displays Based on All-Organic ElectrochemicalSmart Pixels Printed on Paper" Adv
Mater 2002, 14, (20), 1460-1464.[6] Huitema, H. E. A.; Gelinck, G. H.; van der Putten, J. B.
P. H.; Kuijk, K. E.; Hart, C. M.;Cantatore, E.; Herwig, P. T.; van Breemen, A. J. J. M.; de
Leeuw, D. M. "Plastic transistorsin active-matrix displays" Nature 2001, 414, (6864), 599
31
Recommended