TOKYO, May 30 /PRNewswire/ -- Toshiba Corporation today announced that it
has developed the world's first prototype of a full-color polymer organic
light emitting display (OLED), a 2.85-inch display supporting 260,000 colors
in Q-CIF format and a 64-level (6-bit) gray scale. The breakthrough display
was achieved by development of technology for forming a light-emitting polymer
film on a low temperature polysilicon thin film transistor (TFT) array. The
company expects to commercialize OLED in April 2002.
An OLED displays data via an organic light-emitting diode in the pixels
formed on a TFT array. The display itself emits light and has no need of the
backlight required by LCDs, opening the way to thinner, lighter display panels
that consume less power. OLEDs also offer the faster response time required
for motion pictures and support a wider viewing angle.
Toshiba developed its prototype display by combining a breakthrough in the
OLED manufacturing process with technologies it developed in pioneering
low-temperature polysilicon TFT LCDs.
All OLEDs commercialized to date are mono-color or area-color, and use
small molecules in the light-emitting organic film rather than polymers. They
require vacuum-evaporation technology in the production process, which is
unsuitable for the fabrication of large-sized, high-resolution displays on a
large mother glass substrate, as required in the TFT production process.
Toshiba has overcome these limitations with the development of new ink-jet
printing and solvent-material technologies for depositing a polymer film.
Both advances can be applied to the achievement of high resolution displays
and efficient mass production without any need for a vacuum environment.
Like LCDs, OLEDs fall into two broad categories, passive-matrix and
active-matrix displays. A large-sized, full color OLED requires an active
matrix driver in respect of panel lifetime, power consumption and picture
quality. The high level of carrier mobility required for driving OLED in the
active matrix TFTs can be realized only by polysilicon, not by amorphous
silicon. Toshiba established such technology in the process of becoming the
world's first manufacturer of low temperature polysilicon TFT LCDs, and has
transferred it to the OLED.
Toshiba expects to start production of OLEDs in fiscal 2002. Production
will initially target cellular phones and small- and medium-sized PDAs, and
then medium- and large-sized displays, including high-end portable PCs that
requires higher resolution and a gradation surpassing a 64-gray scale.
Toshiba's OLED will be exhibited at the Society for Information
Display (SID) 2001 at San Jose, California, from June 5 to 7, 2001.
Pixel Number 144RGB x 176 (Q-CIF)
Pixel pitch 0.318 x 0.318 millimeter (80 pixels per inch)
Display Size 2.85-inch
Gradation 64-gray scale; 260,000 colors
Corporate Communications Office
SOURCE Toshiba Corporation