3. INTRODUCTION TO LEP
It is a polymer that emits light when voltage is applied to
it.
The structure comprises of thin film semi conducting
polymer sandwiched between anode and cathode
4. 1950 : Bernanose applied high voltage alternating
current to thin film
1977 : conducting polymers are discovered
1990 : Fried invented new Light Emitting Polymers
called as PPV
Birth of “LIGHT EMITTING POLYMERS”!!!!!!!!
5. Thin film of semiconducting
polymer sandwiched between
an ANODE and CATHODE.
ANODE: ITO(Indium Tin
Oxide)
CATHODE: Metals (depends
upon the type of LEP)
SUBSTRATE: Glass, clear
plastic (depends upon the
type of LEP)
Voltage is applied between
anode and cathode
Metal Cathode
Polymer
Glass Substrate
Transparent Anode (ITO)
6. Due to applied voltage
electrons and holes will
migrate to polymer lattice.
They will combine together
to form excitons
Excitons returns to initial
state by emitting radiation.
9. 1. Spin coating process:
In this a glass substrate is spinned at a fixed
angular velocity on which a plastic solution is poured.
10. 2. Printer based Technique:
LEPs can be patterned using a wide variety
of printing techniques. The most advanced is ink
jet printing with a resolution as high as 360 DPI.
11. Operates with 3.3volts only
As active material is plastic cost is much
less than CRT, LCD.
Greater power efficiency than all other
flat panel displays
Life time of more than 30,000 hours
Can be viewed at any angle
Fast switching speed i.e. 1000 times
faster than LCDs.
Higher luminescence efficiency
12. Voltage drops may affect the performance.
Limited market availability.
Aging of LEP
Degradation of luminescence
Light intensity gradually decreases.
Disintegrate due to contact with oxygen.
13. Multi or full color cell phone display
HD Television display
Light weight wrist watches
Military applications
Aircraft cockpit instrumentation
14. Have both electrical and optical property
A low cost solution for flat panel display.
Many manufactures are working to introduce a revolutionary
changes in the market.
Hazardless to environment.
Simpler and cheaper
Have some limitations
Till it is the superior technology………
for the future…..
15. 1. NEWS & INFORMATION
Imagine a day when you are reading a newspaper that is capable of
showing pictures and video, is continuously updating itself with the latest
news via WI-FI connection, and is also so thin and flexible that you can
roll it up put it in your backpack or briefcase.
16. 2.ADVANCEMENTS IN THE HOME
ONE OF THE MANY POSSIBILITIES IS TO REPLACE REGULAR WALLS OR
WINDOWS WITH SIMILAR SIZED OLED INSTALLATIONS WHICH WILL “
LEAD TO USER-DEFINABLE WINDOW SPACES”.
THESE WALLS WILL USE TRANSPARENT OLEDS THAT WILL MAKE IT
POSSIBLE TO HAVE CERTAIN AREAS OPAQUE WHILE OTHER AREAS
CLEAR , DEPENDING ON WHAT THE HOMEOWNER WOULD LIKE.
