|
 Home
Technology
Application & Market
Intellectual Property
Publications-Invited talks-other
Patents
News
Management
Consulting Services
on Flat Panel Displays
Expert Witness for
Patent Infringement
Contact
|
Technology:
Organic Light Emitting Diode (OLED) technology emerges as challenger to
Active Matrix Liquid Crystal Display (LCD). Our company focuses on exploiting
OLED technology not for competing with LCD but to enable small area LCDs
enhance their screen quality in terms of super brightness and high color
quality. Our product is OLED backlight for LCD used in cell phone and digital
cameras. Cell phone hand-sets will become thinner with our OLED backlight.
Our technology is based on ‘small molecule OLED’ and will outperform LED
backlights currently being employed in cell phones and digital cameras. The
assembly using our OLED backlight will be simpler because of our light source
being intrinsically flat compared to LED bulbs. The brightness will be
uniform over the entire area of screen with our OLED backlight. White
spectrum emitted by our OLED backlight is superior to the white spectrum
emitted by white LEDs and thus provides a superior color quality of pictures
seen on cell phone screen and digital camera screen.
Our first generation of OLED backlight is based on thin glass substrates
which makes the cell phone hand-sets thinner. Our second generation will be
based on flexible substrates which are four times thinner than glass
substrates and reduce the weight of the cell phone hand-sets in addition to
the thickness. This will be a huge advantage to cell phone hand-set
assemblers as well as end-users.
Our technology employs multi-layer organic thin films based on ‘small
molecule’ as the core of the device for light emission. A cross-section of
our device of first generation and second generation is shown in the
following Figures 1 and 2.
Fig. 1: First Generation OLED backlight
Fig. 2: Second Generation OLED backlight
An exploded view of our OLED backlight is compared with the current LED
backlight in cell phones as shown in Figure 3.
Fig. 3: Simplicity of OLED backlight
The advantage in terms of simplicity in assembly and compactness is clear
from the Figure3. Assembly is further simplified because our OLED backlight
is a single flat light source unlike LEDs which are four in number per
backlight assembly and require brightness selection process (‘binning’) due
to their non-identical individual nature. In our OLED backlight no such
‘binning’ is necessary.
The spectrum emitted by our white OLED backlight is compared in Figure 5 and
6 with white LED.
|
Fig. 5: White LED Spectrum
|
Fig. 6: White OLED Spectrum
|
It is clear that our white OLED backlight has a rich red and green
spectrum and thus provides superior color quality to cell phone screen and
digital cameras. The advantages of our white OLED backlight of 1.5” diagonal
over conventional white LED backlight, for application to cell phone handset,
are shown in Table I.
Table I: 1.4” diagonal size
|
Parameter
|
LED
|
OLED
|
OLED Advantage
|
|
Average Brightness
|
3000 nits
|
3800 nits
|
25% Brighter
|
|
Thickness
|
2 - 3 mm
|
0.8 mm (1st Gen)
0.2 mm (2nd Gen)
|
Thinner handset
|
|
Color Spectrum
|
Poor in red and green
|
Rich in red and green
|
High color quality picture on cell phone screen.
|
|
Voltage
|
10.8V 3 in series
|
3 - 7V
|
Lower voltage
|
|
Brightness Uniformity
|
65 - 75%
|
>90%
|
Better quality picture
|
|
Backlight Unit
|
Rigid plastic
|
Rigid glass or flexible plastic
|
Versatility in application
|
|
Thermal Stability
|
Problems above 60°C
|
Stable up to 100°C
|
Usable in harsh environments
|
|
Assembly
|
Complex: as high as 6 optical components
|
Simple:
One unit
|
Assembly cost savings $0.25 per unit
|
|
Organic Lighting Technologies LLC