Fujitsu has developed a flexible LCD panel that can maintain the displayed image
even with no power supply, it says.

The cholesteric LCD panel, which is the name given to the technology that allows
the image to be maintained on-screen, measures 3.8 inches across the diagonal
and was on show Thursday at the company's Fujitsu Forum 2005 event in Tokyo.

It's the result of about 5 years of research, says Toshiaki Yoshihara, a senior
researcher at Fujitsu Laboratories' storage and intelligent systems laboratory, and
one of the developers of the panel. He estimates it could be ready for
commercialization in 2 or 3 years.

Two versions of the 3.8-inch display were on show. A powered, color display was
showing continuously changing images, with each screen refresh taking several
seconds, while a monochrome display that hadn't been powered for two weeks was
still showing its image.

Also on Display
Also on show were larger panels about 12 inches across the diagonal. They were
built on glass substrates and so weren't flexible. Fujitsu was showing these in a
mock bus-stop sign that continually changed to show the location of buses, the
timetable, and other information. The company has dreamed up a number of other
uses for the panels, including as electronic advertisements on trains and as
displays on smart cards.

Because they require very little power to refresh, the images can be changed by
drawing power from the weak radio waves used in contactless smart cards, like
those in use on many public transport systems around the world.

Fujitsu is calling the technology 'electronic paper' and also suggested, as do most
companies that propose flexible displays, that it might serve in the future as an
electronic newspaper. While the displays have high contrast and are flexible almost
like paper, they fall short in some areas: they can't be folded and they can't be
written on.

Cholesteric LCD panels are also being developed by other companies including
Philips Research. In addition, Kent Displays, based in Kent, Ohio, already offers
seven types of such panels including an SVGA-resolution (800 pixels by 600 pixels)
panel that measures 14.5 inches by 10.9 inches.
By Jennifer LeClaire
11/28/05 1:34 PM PT

With its new display, Samsung said it has overcome daunting problems involving
the plastic substrate's heat sensitivity including a previous challenge to maintain the
display's substrate thickness when subjected to typical commercial thermal

Samsung Electronics  today said it has developed the world's largest transmissive
TFT LCD (thin-film transistor, liquid crystal display), with high enough resolution to
display digital television content. The new display is double the size of Samsung's
flexible LCD display prototype announced in January 2005.

Samsung said the seven-inch, 640x480 flexible display uses a transparent plastic
substrate that is thinner, lighter and more durable than the conventional LCD glass
panels used today. Moreover, the electronics giant said the full-color transmissive
LCD panel maintains a constant thickness even when it is bent.

Solving an LCD Challenge
Considered the next-generation in flat panel displays, this technology involves the
use of pliable plastic instead of rigid glass substrates in TFT-LCD production.
Samsung said the plastic will not break when flexed, allowing much greater
freedom in commercial designs requiring flexible full-color, high-resolution display

ISuppli Vice President Paul Seminza told TechNewsWorld that there has been
significant research conducted in the area of flexible displays. That's because it has
been a challenging problem to solve since LCDs are designed with the liquid
crystal material sandwiched between two substrates.

"Typically when you flex an LCD it changes the spacing between those substrates.
The spacing is important to the operation of the LCD as a whole. When you flex the
display it looks different near the bend than it does at the edges," Seminza said. "So
figuring out a way to hold the spacing while enabling flexibility has been a big

Low-Temperature Technology
With this advancement, Samsung said it has also overcome daunting problems
involving the plastic substrate's heat sensitivity including a previous challenge to
maintain the display's substrate thickness when subjected to typical commercial
thermal conditions.

Samsung said it has developed a low-temperature processing technique that can
be used to manufacture the display's amorphous thin-film transistors, color filters
and liquid crystals at process temperatures much lower than standard
glass-based, amorphous silicon (a-Si) technology.

Drawing on technology adopted for the production of low-temperature (less than
130 degrees Celsius) a-Si TFT LCD and color filter, Samsung said its proprietary
LCD technology minimizes substrate deformation by preventing not only changes in
thickness but also distortion of images by binding two extremely-thin panels
together through a new proprietary system design.

Targeting Mobile Displays
Samsung said the seven-inch flexible TFT-LCD is optimized for mobility
applications, including cell phones and notebook computers. The company said
system  designers and OEMs also may apply the advanced Samsung display
technology to new applications, such as fashion-enhancing or wearable electronic
display designs, thanks to its differentiated flexible format.

Seminza said mobile applications make sense because mobile devices need to
have a rugged nature. If the LCD display is bendable, he said, then consumers
could throw it in a purse or satchel without worrying about pressure from other
items damaging the display.

"We are constantly looking at how people would utilize that flexible nature," Seminza
said. "Would manufacturers make equipment that actually has curves in it, like a
product that goes around your wrist or a wave shape on a cell phone? Or perhaps
something that wraps around an automobile dashboard that utilizes the curve of the
design? Those are all possibilities."  


工研院展出7吋彩色主動液晶顯示器,與一般顯示器不同的地方,在於捨棄傳統TFT LCD






Sci-Tech-Prod (Science-Technology-Products) Village: 科學技術產品村: 018
Flexible LCD  可彎曲軟性液晶顯示器
received from Pi-Twan Huang 黃碧端
Fujitsu Shows Flexible LCD
Samsung Develops Flexible LCD Display
文/蘇文彬 (記者) 2007-07-06
Fujitsu Shows Flexible LCD
Panel can continue to display an image even
when no power is supplied.
Martyn Williams, IDG News Service
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