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OLED technology is based on layers organic
(carbon-based) chemical compounds that emit light when an electric
current flows through the device. OLEDs are emissive devices, which
mean they create their own light, as opposed to liquid crystal
displays, which require a separate light source (backlight). As a
result, OLED devices use less power and can be capable of high, higher
brightness and fuller color than liquid crystal microdisplays.
Further power economies will be provided by Phosphorescent OLED (PHOLED)
technology developed by UDC. PHOLEDs will attain up to four times greater efficiency than previously
thought possible. Using the principle of electro-phosphorescence to
convert up to 100% of the electrical energy in an OLED into light,
such devices could be four times more efficient compared to current
(fluorescent) OLED technology and up to ten times more efficient than
backlit liquid crystal displays (LCDs).
OLEDs are "imprinted" on a silicon substrate. Since OLED is self
luminescent and does not require back-lighting for operation, it is
consuming significantly less power than alternative Liquid Crystal
Displays (LCD). The active matrix silicon integrated circuits are
imprinted directly under the display controlling the power to each
organic point of light diode (pixel), performing certain image control
functions at very high speed. OLEDs capability to refresh in
microseconds rather than milliseconds, as LCD displays do, contribute
to virtually flicker-free display in near-eye applications, resulting
in smooth display even with highly dynamic motion video.
OLED technology has several advantages to the military user - since
solid-state OLED displays do not use liquid crystal fluids, they
instantly switch images on and off even at low temperatures (-40
degrees C) preventing image fade out at high temperatures (+65
degrees C). The OLED concept, patented by Kodak is not new, however,
only in recent years it matured into practical technology, especially
with the use of more efficient barrier layers (glass and other
plastics), lower cost and extended lifespan of the
luminescent organic materials.
In an effort to solve one of the critical OLED
limitations, eMagin Corporation and the University of Michigan’s
Solid-State Electronics Laboratory (SSEL) are studying novel
approaches for thin-film encapsulation to enable the production of
small, lightweight rugged displays and, potentially, flexible OLED
displays. The program is funded by the Office of Naval Research as a
Small Business Technology Transfer (STTR) rugged and reliable
thin-film encapsulation method for OLED displays. According to Susan
Jones, executive vice president and chief marketing officer, at eMagin,
this research could foster new generations of rugged, lower cost
encapsulation techniques that could be applied to the production of
micro-displays as well as larger format OLED devices.” |
