OLED technology uses organic light emitting diodes to create brighter, thinner, and more flexible displays. An OLED is composed of thin films of organic molecules that emit light when electricity is applied. The first OLED was developed in 1987, and since then OLEDs have been used in various displays. OLEDs offer advantages over LCDs like higher contrast, better viewing angles, and less power consumption. Major applications of OLEDs include televisions, smartphones, and laptops.
INTRODUCTION
Uses organiclight emitting diode(OLED).
Emerging Technology for displays in devices.
Main principle behind OLED technology is
electroluminescence.
Offers brighter, thinner, high contrast, flexible
displays.
3.
WHAT IS ANOLED?
OLEDs are solid state devices composed of thin
films of organic molecules that is100 to 500
nanometres thick.
They emits light with the application of electricity.
They doesn’t require any backlight. i.e., they are
self emitting.
They are made from carbon and hydrogen.
4.
HISTORY
The firstOLED device was developed by Eastman
Kodak in 1987.
In 1996, pioneer produces the world’s first
commercial PMOLED.
In 2000, many companies like Motorola, LG etc
developed various displays.
In 2001, Sony developed world’s largest fullcolor
OLED.
5.
HISTORY (CONTD.)
In2002, approximately 3.5 million passive matrix
OLED sub-displays were sold, and over 10 million
were sold in 2003.
In 2010 and 2011, many companies announced
AMOLED displays.
Many developments had take place in the year
2012.
6.
FEATURES
Flexibility.
EmissiveTechnology.
Light weight and thin.
Low power consumption.
High contrast, brighter and perfect display from all
angles.
7.
STRUCTURE OF OLED
Substrate.
Anode.
Organic layer.
-Conductive layer (Hole Transport Layer).
made up of polyaniline or metal-phthalocyanine.
-Emissive layer( Electron Transport Layer).
made up of polyfluorene or metal chelates.
Cathode.
OLED FABRICATION
Substratepreparation.
Device deposition
Deposit and pattern anode.
Pattern organic layers.
Vacuum deposit and pattern cathode.
Encapsulation.
Also involves making backplane.
10.
OLED DEPOSITION
Organiclayers can be applied to the substrate
using the following methods.
- Evaporation and shadow masking.
- Inkjet printing.
- Organic vapor phase deposition.
COLOUR GENERATION
Differentapproaches for fabricating red, green and
blue pixels.
- Red, green and blue individual pixels.
- White emitter and colour filters.
- Blue emitter and colour converters.
- Stacked OLED
WORKING PRINCIPLE
Avoltage is applied across the anode and cathode.
Current flows from cathode to anode through the
organic layers.
Electrons flow to emissive layer from the cathode.
Electrons are removed from conductive layer
leaving holes.
Holes jump into emissive layer .
Electron and hole combine and light emitted.
OLED ADVANTAGES
Thinner,lighter and more flexible.
Do not require backlighting like LCDs.
Can be made to larger sizes.
Large fields of view, about 170 degrees.
Faster response time.
Brighter.
High resolution, <5μm pixel size.
CONCLUSION
Organic LightEmitting Diodes are evolving as the
next generation displays.
As OLED display technology matures, it will be
better able to improve upon certain existing
limitations of LCD including
high power consumption
limited viewing angles
poor contrast ratios.