Oled
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Transcript of Oled
OLED
Presented byT.Spandana & R.G.Srujana
3rd year,E.C.ESHRI SAI INSTITUTE OF ENGINEERING AND TECHNOLOGY
Contents IntroductionWhat is OLED?Birth of OLEDHistoryArchitecture of OLEDHow OLED works?Types of OLEDsAdvantages and disadvantagesCurrent, future scopeConclusion
IntroductionImagine having high-definition TV 8O inches wide less than a quarter inch thick
consume less power & can be rolled up when u are not
using
Is it possible??
Yes, it is possible by using OLED technology
Before technologies In this field first came the small LED displays (which can
show only the numeric contents)
Then came heavy jumbo CRTs ,which are used till now.
the problem is they are very heavy, bulky, couldn’t carry
them form one place to other place.
Next to CRTs LCDs came into existence. which are lighter
in weight compare to CRTs. the drawback in LCDs is the
efficient result is obtained only in some particular
directions.
What is OLED?
OLED - Organic Light Emitting Diode
An OLED is any light emitting diode (LED) which emissive electroluminescent layer is composed of a film of organic compounds.
Birth of OLED
First successfully created by Ching
Tang and Steve Van Slyke in 1987 at
Kodak Labs.
First tests – very efficient, simple to
make
Showed potential for displays
HistoryFirst developed in the early
1950s in France1960s-AC-driven
electroluminescent cells was developed
In 1987 Chin Tang and Van Slyke introduced the first light emitting diodes from thin organic layers.
In 1990 electroluminescence in polymers was discovered.
Architecture of OLED Substrate:(clear plastic, glass,
foil) - The substrate supports the OLED.
Anode(transparent):The anode removes electrons (adds electron "holes") when a current flows through the device.
Cathode (may or may not be transparent depending on the type of OLED) - The cathode injects electrons when a current flows through the device.
Organic layer:
o Conducting layer-This layer is ma-de
of organic plastic molecules that
transport "holes" from the anode. One
conducting polymer used in OLEDs is
polyaniline.
o Emissive layer - This layer is made of
organic plastic molecules (different
ones from the conducting layer) that
transport electrons from the cathode;
this is where light is made. One
polymer used in the emissive layer is
polyfluorene.
How OLED works?
Types of OLEDsPassive-matrix OLED
Active-matrix OLED
Transparent OLED
Top-emitting OLED
Foldable OLED
White OLED
Passive-matrix OLEDPerpendicular cathode/anode strip orientationLight emitted at intersection (pixels)External circuitry• Turns on/off pixels
External circuitryLarge power consumption• Used on 1-3 inch screens• Alphanumeric display
Active-matrix OLEDFull layers of cathode, anode, organic moleculesThin Film Transistor matrix (TFT) on top of anode• Internal circuitry to determine which pixels to turn on/off
Less power consumed then PMOLED• Used for larger displays
Transparent OLEDTransparent substrate, cathode and anodeBi-direction light emissionPassive or Active Matrix OLED Useful for heads-up display• Transparent projector• Screen• glasses
Top-emitting OLEDNon-transparent or
reflective substrate
Transparent Cathode
Used with Active
Matrix Device
Smart card displays
Foldable OLED
Flexible metallic foil
or plastic substrate
Lightweight and
durable
Reduce display
breaking
Clothing OLED
White OLED
Emits bright white
light
Replace fluorescent
lights
Reduce energy cost
for lighting
True Color Qualities
Advantages Much faster response time Consume significantly less
energy Able to display "True Black"
picture Wider viewing angles Thinner display Better contrast ratio Safer for the environment Has potential to be mass
produced inexpensively OLEDs refresh almost 1,000
times faster then LCDs
Disadvantages Lifetime
› White, Red, Green 46,000-230,000 hours About 5-25 years
› Blue 14,000 hours About 1.6 years
Expensive Susceptible to water Overcome multi-billion dollar LCD
market
Current Research for OLEDso Manufacturers focusing on
finding a cheap way to produceo "Roll-to-Roll"
Manufacturing o Increasing efficiency of blue
luminance
Applications of OLEDs TVs Cell Phone screens
Computer Screens
Keyboards (Optimus
Maximus) Lights Portable Divice displays
Future Uses for OLEDLighting• Flexible / bendable lighting• Wallpaper lighting defining new
ways to light a space• Transparent lighting doubles as a
window
Cell Phones• Nokia 888
Scroll Laptop• Nokia concept OLED Laptop
Conclusion
Research and development in the field of
OLEDs is proceeding rapidly .
And this may lead to the future application in
heads-up displays, automotive dashboards,
billboard type displays, home and office
lightings and flexible displays .
THANK YOU
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