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Innovations in Toshiba’s Screen Technologies
Table of Contents
Innovations in Toshiba’s Display Technologies......................................................... 1
The LCD: Today’s Display of Choice ......................................................................... 1
The Latest in Notebook and Workstation LCD Technologies ................................ 1
How the LCD works ...................................................................................................... 2
Pixel Perfect: On the road to UXGA .......................................................................... 3
Sunglasses at Night: Transmissive, Reflective and Transflective Light Sources.... 4
Reflective LCD........................................................................................................... 5
Transflective LCD ...................................................................................................... 5
Screen Technologies for Today and Tomorrow....................................................... 5
Ultra-high-resolution displays: polysilicon TFT LCDs .............................................. 6
Plasma displays: Toshiba brings the future of digital TV home to you.............. 6
Digital Light Processor: “Mirror, Mirror on the Wall…”.......................................... 7
Light-emitting Diode (LED) Displays: From Pilot Lights to White Light................ 8
From LED to OLED: Toshiba’s LEP displays ............................................................. 8
An Overview of Video Standards ............................................................................ 10
Selected Sources.................................................................................................. 10/10
Innovations in Toshiba’s Display Technologies
Toshiba’s Satellite® 5100 multimedia notebook, featuring a 15” Super Fine Screen
UXGA (Ultra Extended Graphics Array) display provides high resolution, enhanced
viewing from a wide angle and double the contrast ratio of the conventional display.
With fast responses times and high-colour fidelity, this notebook is ideal for watching
full-motion video, working with graphics applications or delivering stunning
presentations. This innovative Liquid Crystal Display (LCD) comes as no surprise, as
Toshiba has long had a record of delivering state-of-the-art displays to its customers.
In 1985, Toshiba released the first commercially successful notebook, the T1100,
overcoming the challenge of creating a clearly legible display for mobile products.
In 1986, Toshiba demonstrated the first active-matrix standalone LCD, supporting 8
colours and 640 x 480 pixels. In this article, we explore how LCD technology has
evolved since then, as well as looking at alternative display technologies that offer
Toshiba customers a state-of-the-art viewing experience across a range of products,
including televisions, PDAs, notebooks, displays, videowalls, televisions and flat
panels. Finally, we take a look at emerging display technologies, and explore how
Toshiba continues to be one of the leaders in this field.
The LCD: Today’s Display of Choice
When notebooks were originally introduced in the 80’s, most of them came with
monochrome, passive-matrix LCD screens. These displays met many of the
requirements that are still important for notebook users today: the LCDs were lighter,
smaller, and required less power than a CRT (cathode ray tube).
However, in the early years, most mobile users were happy to switch to an external
CRT monitor when working in the office. At that time, CRT monitors still offered many
advantages as compared to the early TN (twisted nematic) LCDs. Conventional
displays offered higher resolution, most of them supported colour, and presented the
user with a much wider viewing angle. Indeed, with early LCDs, for optimal viewing,
users had to sit directly in front of the TN LCD.
Moreover, the early LCDs were subject to such effects as “ghosting” (as the cursor
moves across the screen it leaves a trail of images scattered behind it) or
“submarining” (the cursor-image disappears entirely as it moves across the screen).
Even the enhanced DSTN displays suffered from these effects. It was not until active
matrix displays emerged that LCD technology really matured.
Today, due to advances in LCD technologies, the situation is reversed. LCD displays
now truly outperform CRTs in almost all categories, making them ideal for notebooks,
as well as high-end state-of-the-art displays. In addition to being light and compact,
as well as consuming less power than a CRT, LCDs provide flicker-free images, offer a
higher pixel-density (200 pixels per inch), and support high video resolutions.
The Latest in Notebook and Workstation LCD
Technologies
Of course, as the number of pixels and supported colours increase, the amount of
memory and processing power required to redraw the screen and support complex
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imaging also increases. So, it is appropriate to choose a display technology that
meets the requirements of the device and the user. Here it is useful to compare some
of the LCD panels for workstation and notebook use.
For instance, Toshiba’s 20.8-inch flat-panel TFT LCD is designed for workstation use as
a desktop display. It supports up to 3,200 by 2,400 pixel QUXGA (Quad Ultra Extended
Graphics Array) resolution, displays up to 16.77 million colours and has 7.7 million
pixels. With a screen large enough to display a full A3-sized sheet of paper, these
LCDs are used in various sectors, including science, banking, engineering, publishing
and medicine, where users require screen images that are as clear as an original
photograph. The display can be used for applications such as creating maps and
engineering drawings, the analysis of aerial and satellite photographs, and viewing
complex documents, such as patent applications, all of which demand precise
images and large displays. In fact, the image quality of the new display is high
enough to reproduce works of art.
Although the 20.8-inch flat panel display is very narrow (mm), it weighs 14kg, making
it unsuitable for notebooks. For today’s notebook user, UXGA is an optimal
technology. With a resolution of 1600 x 1200, approximately 1.9 million pixels, this
display outperforms XGA and SXGA standards. Compared with an XGA panel, an
UXGA display has more than 1.1 million additional pixels. As well, combined with
Toshiba’s Super Fine Screen, the display offers a high contrast ratio, high brightness
and short millisecond response times.
With a wide viewing angle, Toshiba’s 15” UXGA display offers remarkably detailed
and precise images that have almost print-like clarity. These notebook LCDs are ideal
for the following applications: 3D gaming, multimedia applications, watching movies
and digital image editing/viewing.
Whether implemented in notebooks or used as flat panel displays, LCDs offer both
notebook and desktop users enhanced viewing and usability features. To
understand what makes this development possible, we need to take a step back
and look at how LCD panels work, and how they have evolved.
How the LCD works
The Radio Corporation of America (RCA) introduced the first prototype LCD in the
1960’s, made of twisted nematic (TN) liquid crystal. Originally, most screens made use
of twisted nematic (TN) liquid crystal, but enhancements, such as super twisted
nematics (STN), dual scan twisted nematics (DSTN), ferroelectric liquid crystal (FLC)
and surface stabilized ferroelectric liquid crystal (SSFLC), have subsequently been
introduced. While these enhancements have significantly improved the user’s
viewing experience, the basic principle of the LCD remains the same.
Liquid crystals are naturally twisted, but applying an electric field will untwist them to
varying degrees, depending on the applied voltage. When the liquid crystals
straighten out, they change the angle of the light passing through them. Thus,
potentially, each crystal is like a shutter that can either allow light to pass through or
block the light. By selectively supplying voltage, the LCD harnesses this potential to
block or display light in order to create the desired image on the screen. To produce
an image, glass embedded with a grid of electrodes sandwiches the liquid crystals,
allowing the individual pixels to be turned on or off.
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This grid is part of the glass substrate and functions differently depending whether
passive or active matrix technology is used. Passive screens use a grid of horizontal
and vertical wires to apply voltage. The horizontal grid is attached to one of the glass
layers and the vertical grid to the other glass layer with the liquid crystal cells
sandwiched between them. Each intersection constitutes a single pixel that can
either pass or block light, depending on the applied voltage.
Whereas passive-matrix displays use no transistor to drive each row and each
column on the screen, active-matrix screens use at least one transistor to drive each
pixel. Tiny transistors and capacitors are etched onto the glass substrate at the
intersection of each row and column.
For a colour display, the pixel is further separated into three using a red, green or
blue filter; these colours are mixed in varying intensity to produce a full palette of
colours on the screen. Colour displays require an enormous number of transistors. For
example, a colour display with a resolution of 1,024 by 768 pixels requires 2,359,296
transistors (1024 columns x 768 rows x 3 cells) etched onto the glass.
To give you a clear picture of how this LCD sandwich looks, here are the six layers
that make up a colour TFT (thin film transistor) display (the order of layers may differ
depending on the screen manufacturer and production process):
•
•
•
•
•
•
backlight to generate light which flows to the surface of the display
first polarising filter
glass substrate with thin film transistor
liquid crystal
glass substrate with colour filter
second polarising filter
Throughout the development of the LCD panel, real enhancements and
performance advantages have been won by changing the grid or matrix controls,
the angle and flow of light, as well as by enhancements in the liquid crystals.
Pixel Perfect: On the road to UXGA
For many years, passive-matrix displays underwent a number of enhancements.
However, the major revolution in LCD technology came with the introduction of the
active-matrix display, making it easy for notebook users to rely on their LCD whether
on the road or in the office.
Here is an overview of some of the major LCD enhancements, leading to today’s
active-matrix UXGA display:
• TN uses a 90-degree twist to the molecules between one alignment layer and
the other. These screens offer black imaging on a grey background and very
limited viewing angle. To see the image on the screen, the user must be
directly in front of the screen.
• STN displays improve on TN screens by increasing the rotation of the molecules
in their off state from 180 to 260 degrees. This brings a higher contrast ratio and
higher resolution to larger screens and offers a greater viewing angle. Yellowgreen and blue were originally possible.
• Coloured STN displays (CSTN) are possible.
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•
•
•
•
DSTN screens are an enhancement of STN. DSTN divides the screen in two and
scans each half simultaneously, thereby doubling the number of lines
refreshed. Greater clarity is possible for DSTN, but it still suffers from a 'ghosting'
effect that often causes a moving cursor to leave a trail of spectral images
behind it.
High-Performance Addressing (HPA) screens provide faster refresh rates, offer
high resolution and provide better contrast than other passive-matrix displays.
Triple Super Twisted Nematic (TSTN) uses a high polymer, double refraction film
to create black-and-white LCDs of exceptional quality. The single-layer
compensation film is called FSTN (Film Super Twisted Nematic), providing a
better contrast ratio and the better viewing angle than TN or STN.
TFT screens are faster and provide a much brighter, sharper, high contrast
image. As well, they offer a wider viewing angle, and deliver richer colours
than passive displays. Practically all notebook displays and LCD monitors now
on the market use TFT technology. However, there are some drawbacks; as
each pixel has a transistor, the power required is greater than with a passivematrix display. Also, until recently, TFT screens often displayed dead pixels. Well
into the 1990’s, manufacturing quality standards still tolerated anywhere from
5-15 defective pixels per screen.
Today’s UXGA display takes advantage of several significant innovations in the
evolution of LCD technology. In the past, the transistor that controls each pixel took
up around 50 percent of the pixel's surface area, requiring a powerful backlight to
shine through the transistor (particularly when you consider the number of pixels
required for a UXGA display).
However, with today’s tinier transistors, the power and intensity of backlighting can
be used to enhance the viewable image. By introducing a special optical film on the
front of the display to spread the image over a wider angle, a bright image is
viewable at up to approx. 140 degrees. As well, enhanced liquid crystal materials
support greater climate extremes and higher contrast ratios. Finally, enhancements
in the production process have all but eliminated the chance of seeing dead pixels
on the TFT display.
Sunglasses at Night: Transmissive, Reflective and
Transflective Light Sources
Most of us are familiar with the concept of polarised light in the form of Polaroid®
sunglasses. For LCDs, polarisation is a process that allows light to pass through, only if
it is oriented in the right direction. For instance, Polaroid® sunglasses are designed to
allow through only vertically polarised light. This means that it makes sense to wear
sunglasses when driving on wet roads at night as it cuts down on road reflection: this
is because light reflected from a wet road is polarised horizontally and hence, the
reflected light will be filtered out by Polaroid® sunglasses. So, while it may seem cool
to some to wear their sunglasses at night, it can also be practical.
When it comes to LCDs, there are three kinds of polarised light transmissions that are
particularly important, namely transmissive (the kind of LCDs we have been talking
about up until now), reflective and transflective. Transmissive LCDs use a transparent
rear polariser and a light source from behind the display (backlight), and are wellsuited for indoor use and office lighting. Transmissive LCDs are installed in Toshiba
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notebooks and available also in the form of the 20.8-inch flat panel display. Now,
let’s look at some innovations in reflective and transflective displays used by Toshiba.
Reflective LCD
For reflective LCDs, light enters from the front, hits a reflector and a polariser at the
rear, and bounces back to the user. This type uses the least power. As the rear
polariser does not allow any light to pass through and not backlight is used.
Removing the backlight from the display cuts by one-third the amount of power
consumed by the device - an important factor in mobile devices that have a limited
battery life. As well, the removal of the backlight also means the panel weighs
around half as much as a conventional unit. This makes the reflective LCD ideal for
such products as wristwatches, calculators and other tiny devices, such as Toshiba’s
Pocket PCs. Toshiba’s Pocket PCs offer users a 4-inch color reflective lowtemperature polysilicon type thin-film transistor LCD panel.
Transflective LCD
Transflective combines the features of transmissive and reflective cells and can be
adjusted to suit the designer's application. The rear polariser has partial reflectivity
and can be combined with a backlight for use in all types of lighting conditions.
Reflected light is used whenever possible and backlight when it is required; this
means that power consumption is considerably reduced as the backlight is not
constantly in use. Devices using transflective LCDs, include mobile phones and Tablet
PCs.
In 2001, Toshiba demonstrated its prototype transflective LCDs at EDEX (Electronic
Display Exhibition) in Tokyo. Available in various sizes, including 4-inch, 8.4-inch and
10.4-inch dimensions, these screens support a wide range of mobile devices. These
low-temperature polysilicon TFT-LCD panels produce images equally well in a variety
of lighting conditions, ranging from bright sunlight to a dimly lit room.
Approximately 80% of the pixels are reflective; the remaining 20% are transmissive.
With this high ratio of reflective pixels, these LCDs can operate independently of the
backlight. This means that the backlight can be used less often, reducing the power
consumption.
With the development of a tinier 2.2-inch screen, Toshiba will also offer LCDs for use in
mobile phones. Perhaps, we can look forward to seeing these LCDs in Toshiba’s own
GPRS phones that will be available on the market in 2002 in Europe.
Screen Technologies for Today and Tomorrow
Finally, we offer a glimpse of display technologies that are important today and will
become increasingly significant in years to come. Firstly, we look at role of Toshiba
Matsushita Display Technology Co., LTD as a leading developer and manufacturer of
polysilicon displays which are enabling the miniaturisation of mobile computing
devices.
Then, we look at emissive technologies where Toshiba Matsushita Display Technology
is actively involved in developing and manufacturing displays. Whereas LCDs are
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non-emissive, meaning that they require a light source and modulate transmitted or
reflected light, emissive displays inherently create light and do not need a separate
backlight to provide light for the image. As such, they open the way for thinner,
lighter designs, as will be seen when we look at the following display technologies:
-
plasma displays
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electromechanical or DLP (Digital Light Processor, originally developed by
Texas Instruments) videowalls
-
LED (light-emitting diode) panels
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organic light emitting displays (OLEDs).
Ultra-high-resolution displays: polysilicon TFT LCDs
Generally, we can expect to see developments in the area of polysilicon LCDs, a
technology that is particularly suited for the miniaturisation of mobile computing
devices, requires less power and supports a greater number of DPI (Dots Per Inch).
Low temperature polysilicon allows electrons to flow faster than conventional
displays, resulting in bright screens capable of higher resolutions. For users, this means
excellent visualisation for graphics, including MPEG4 playback. We can expect to
see these displays used for next-generation video-capable mobile phones, e-books,
PDAs, portable PCs, desktop LCD TVs and monitors and personal DVD players.
With polysilicon displays, it is possible to crowd more pixels per square inch, resulting
in LCDs that approach true print quality. Let’s look at a specific example. Whereas
laser-printed text is 300 dpi or more, most of today’s polysilicon TFT LCDs support
fewer than 100 dpi. By contrast, Toshiba’s low-temperature polysilicon LCDs are
bringing us closer to the printed standard. In 2000, Toshiba announced a 4-inch
display capable of displaying 202 pixels per inch (PPI) VGA resolution and 262,144
colours.
Indeed, polysilicon displays are so legible and light that e-books are now becoming
as easy to read as their printed counterparts. Toshiba Matsushita Display Technology
has also introduced a 7.7-inch display, which supports Microsoft's ClearType® text
resolution enhancement technology and has a resolution of 150 pixels per inch. The
display has a resolution of 640 x 960, can display 262,144 colours, has a contrast ratio
of 250:1, and weighs 150 grams.
Polysilicon displays also allow for more flexible, more reliable and slimmer designs on
account of the fact that the peripheral circuitry can be fabricated along with the
active matrix on a glass substrate. Polysilicon displays are Ideal for Toshiba’s ultra-slim
notebooks, such as the Portégé® 2000: this particular LCD offers a resolution of 1,024
x 768 and is extremely slim at around 4mm.
Plasma displays: Toshiba brings the future of digital TV home to you
Anyone, who has seen images displayed on a plasma screen can attest to the fact
that this wide-angle, bright and richly colourful viewing experience is exceptionally
rich and lifelike. Just what makes the plasma viewing experience so amazing?
These emissive displays use electrodes to excite the gas plasma, which then causes
phosphors in each sub-pixel to produce coloured light (red, green or blue). The
phosphors are the same types used in conventional CRT devices, such as televisions
and standard computer monitors. However, plasma displays eliminate the need for
the long picture tube of a CRT. Instead, a digitally controlled electric current flows
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through a matrix to the pixels where it is required; each subpixel is individually
controlled to produce millions of different colours. This results in a slim, relatively light
display with an excellent digital picture.
While plasma screens are not ideal for notebooks, as they are subject to image
sticking, do not travel well and do not currently support resolutions higher than XGA,
this technology is perfect for digital TV viewing. Indeed, many plasma screens
available today support the 16:9 aspect ratio used by high-definition TV (HDTV) and
wide-screen movies available on DVD. Moreover, you can hang these slim displays
(3.5 to 6 inches thick) on the wall, making the plasma screen ideal for a home
cinema. Unaffected by magnetism, there is no problem placing speakers in any
position around the room for a truly dynamic entertainment experience.
While digital TV is still somewhat of a niche market, the next 10 years will see the
switch to digital broadcasting around the world, increasing the demand for HDTV.
Today, Toshiba already offers a 50-inch wide screen HDTV monitor (50WP16/50HP81).
Only 4 inches thick, it can display a 720p progressive-scan high-definition image in
native resolution on its 1,366 x 768-pixel screen. The aspect ratio control supports both
wide screen 16:9 format and standard 4:3 signals; a contrast ratio of 2000:1 keeps
dark shadows black.
Digital Light Processor: “Mirror, Mirror on the Wall…”
Most of us have seen video walls, used at trade fairs, exhibitions, modern art
installations or stage productions. Rock concerts in particular often use video walls to
project a larger than life image of the performer. Video walls are banks of stacked
monitors or 'projection cubes' that split an image across several screens or can be
used to display multiple images simultaneously. A variety of stackable units and
technologies, including LCD, LED, plasma, CRT and DLP, are currently available on
the market.
DLP is the latest of these technologies and compares favourably to others as it offers
bright images, even in low ambient conditions, and does not suffer from screen burnin. Using mirrors to reflect light, DLP panels offer high contrast, high-resolution images.
Toshiba’s P500DL (50-inch display supports SXGA), P410 and 411DL (41-inch displays)
offer naive SVGA resolution and incorporate a DMD (digital mirror display) chip so
that the “fairest image of them all” appears on the video wall.
The DMD chip is covered with thousands of miniature mirrors. When a signal is sent to
turn a pixel on, a tiny mirror rotates to reflect light towards the screen. When the off
signal is sent, the mirror tilts so that light is reflected away.
To produce colour, light is reflected through a spinning colour wheel. The colour
wheel is a circular sheet of transparent material that is as thin as a piece of paper
and textured with the three primary colours: red, green and blue. This transparent film
rotates in a circular motion so only one colour of concentrated light passes at a time.
The mirrors of the DMD chip turn at a high rate, carefully timed to reflect the
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appropriate coloured light from the colour wheel. This light travels through the lens of
the projector to create high-resolution images, with support for 16.7 million colours.
Light-emitting Diode (LED) Displays: From Pilot Lights to White Light
Most of us are familiar with the humble LED, often used as a red pilot light in
appliances. Other uses include scoreboards at sporting events, clock radios and
calculators. The light-emitting diode (LED) is a semiconductor device that emits
visible light when an electric current passes through it. Typical monochrome outputs
from a LED display include red (at a wavelength of approximately 700 nanometers)
and blue-violet (about 400 nanometers).
Currently, Toshiba manufactures colour LED displays for indoor and outdoor use.
These units are modular, and can be configured according to the user’s
requirements, allowing for the display of multiple images in very large formats. Unlike
the LED displays we have just mentioned, these screens offer 16.7 million colours.
Using blue, red and green LEDs, each of which is controlled by 256 steps of contrast,
these displays support graphic images or realistic video images in full colour.
In 2001, Toshiba also announced a major innovation in LED technology: the white LED
which achieves a short peak wavelength of approximately 380 nanometers. This new
LED offers a high luminosity, low power consumption light source that achieves
luminosity levels sufficient for incandescent lamps. Other applications include the
instrument panels of motor vehicles and LCD backlighting.
The new LED differs from the conventional technology used. Light emission in the
visible wavelength band is controlled by excited phosphors, not by using
temperature changes in the LED, to achieve a change in colour output. A greater
range of operating temperatures and increased control over the image displayed
are two of the main benefits of this enhanced technology.
From LED to OLED: Toshiba’s LEP displays
OLED refers to a broad category of organic light-emitting diode displays. Compared
to LCDs, OLEDs are an emissive technology that does not require a backlight and
have the potential to eliminate a glass substrate in the display, as well as offering fast
response times and supporting a wider viewing angle. As such, OLED promises
thinner, lighter display panels that consume less power than conventional LCDs.
While this technology is still under development and relatively costly, it may one day
replace LCD technology.
OLEDs can be broken down into two categories based on the size of the molecules
in the display materials and differences in the production process. LEP (Light-Emitting
Polymer) uses materials with relatively larger molecules as compared to SMOLED
(Small Molecule Light-Emitting Display). LEP displays data via an organic lightemitting diode, with the pixels formed on a thin film transistor array. Each of these
pixels can be turned on or off independently and can create multiple colours,
resulting in a very fluid and smooth-edged display.
Toshiba Matsushita Display Technology has developed the world's first prototype of a
full-colour LEP display, a 2.85-inch display supporting 262,144 colours in Q-CIF format
and a 64-level (6-bit) gray scale. These active matrix displays will appear initially in
PDAs and mobile phones. We may also see larger displays, including wall-mounted
displays, and notebook screens in coming years.
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However, the most exciting advantage to OLED is the possibility of moulding it into a
form or embedding it in fabric, allowing for flexible design and offering usability
advantages. For instance, in the future, it may enable PDAs that can be rolled up
and stored in one’s pocket. Alternatively you could connect a foldable screen and
keyboard to a mobile computing device, enabling users to more easily enter data
and even gain basic notebook functionality from the PDA. For wearable PCs, this
technology promises to “unfold” as yet untold mobile computing possibilities.
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An Overview of Video Standards
•
VGA -- 640 x 480 resolution, 300,000 pixels
•
SVGA -- 800 x 600 resolution, 480,000 pixels
•
XGA -- 1024 x 768 resolution, 768 pixels
•
SXGA -- 1280 x 1024 resolution, 1.3 million pixels
•
UXGA -- 1600 x 1200 resolution, 1.9 million pixels
•
QXGA - 2048 x 1536 resolution, 3.2 million pixels
•
QSXGA – 2560 x 2048, 15.72 million pixels
•
QUXGA – 3200 x 2400, 7.7 million pixels
Selected Sources
Technology Overview
http://www.pctechguide.com/07pan3.htm
http://www.zdnet.com/pcmag/pctech/content/17/21/tu1721.002.html
http://www.zdnet.co.uk/pcmag/supp/display/
http://www.vnunet.com/Analysis/88978
LCD
http://www.pcworld.com/news/article/0,aid,51944,00.asp
http://www.howstuffworks.com/lcd.htm
http://www.pcworld.com/howto/article/0,aid,15112,00.asp
http://www.toshiba.com/taec/main/faq/lcd_faq.html
http://www.toshiba.co.jp/about/press/2001_03/pr1502.htm
Reflective
http://www.pcworld.com/news/article/0,aid,16258,00.asp
http://www.toshiba.com/taec/press/to-082.shtml
Transflective
http://www.nikkeibp.asiabiztech.com/nea/200107/peri_134206.html
Polysilicon
http://www.toshiba.co.jp/about/press/2000_04/pr1101.htm
http://www.microsoft.com/presspass/press/2000/Jul00/HighResolutionPR.asp
http://www.toshiba.co.jp/about/press/2000_07/pr1001.htm
Plasma
http://www.howstuffworks.com/home-theater9.htm
http://www.federalstereo.com/tos50newmod.html
http://www.ivojo.co.uk/toshiba-50wp16.htm
http://www.dtvcity.com/plasma/toshiba-50hp81.html
DLP
http://www.tlt-uk.co.uk/
http://www.toshiba.com/taisisd/projectors/dlpfaq.htm
http://www.agocg.ac.uk/brief/lcd.htm
http://www.deregle.co.uk/pages/2j.htm
LED
http://www.howstuffworks.com/led.htm
http://www.compoundsemiconductor.net/PressReleases/2001/PR02090101.ht
m
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OLED
http://www.toshiba.com/taec/press/to-128.shtml
http://www.toshiba.com/taec/press/to-146.shtml
http://zdnet.com.com/2100-11-265928.html
http://www.cdtltd.co.uk/STORE/Corporate%20Development/Acronyms_files/A
cronyms%20R1.htm
http://www.ualberta.ca/~kaminsky/organicelectroluminescence.htm
http://www.eetimes.com/story/OEG20010410S0016
Polaroid is a registered trademark of the Polaroid Corporation. Microsoft and ClearType are
registered trademarks or trademarks of Microsoft Corp. Other products and company names
herein may be trademarks of their respective owner.
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