HRH THE PRINCE OF WALES
INSTITUTE OF ENGG. & TECH,
JORHAT, ASSAM
Seminar On
OLED Technology
Submitted by
GYAN JYOTI GOGOI
6TH SEM OF ETC


 Introduction
 What is an OLED?
 History
 Features
 Structure of OLED(Figure)
 OLED Fabrication
 OLED Deposition
 Types of OLED
 OLED Advantages
 OLED Disadvantages
 Applications
 Conclusion
 References
Content

Introduction
 Stands for organic light emitting diode(OLED).
 Emerging Technology for displays in devices.
 Main principle behind OLED technology is
electroluminescence.
 Offers brighter, thinner, high contrast, flexible
displays.

What is an OLED?
 OLEDs are solid state devices composed of thin films
of organic molecules that is 100 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.

HISTORY
 The first OLED 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.

HISTORY (CONTD.)
 In 2002, 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.

Features
 Flexibility.
 Emissive Technology.
 Light weight and thin.
 Low power consumption.
 High contrast, brighter and perfect display
from all angles.

Structure of OLED(Figure)

 Substrate preparation.
 Device deposition
 Deposit and pattern anode.
 Pattern organic layers.
 Vacuum deposit and pattern cathode.
 Encapsulation.
 Also involves making backplane.

Organic layers can be applied to the substrate
using the following methods.
- Evaporation and shadow masking.
- Inkjet printing.
- Organic vapor phase deposition.

 Different approaches 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

Colour Generation(figure)

Working Principle
 A voltage 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.

Working Principle(figure)

OLED device operation
Transparent
substrate
Anode
(ITO)
Conductive
layer
Emissive
layer
Cathode
LUMO
LUMO
HOMO
HOMO
eˉeˉ
h+
h+h+
Light

Six types of OLEDs
Passive matrix OLED(PMOLED).
Active matrix OLED(AMOLED).
Transparent OLED(TOLED).
Top emitting OLED.
Flexible OLED(FOLED).
White OLED(WOLED).
Types of OLED

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.

Expensive.
Lifespan.
Water damage.
Colour balance issues .

Major applications of OLED technology are
 OLED TV, Digital Cameras screens.
 Mobile phones with OLED screens.
 Roll top Laptop etc.
Applications

Conclusion
 Organic Light Emitting 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.

REFERENCES
www.google.com
www.wikipedia.com
www.studymafia.org
www.pptplanet.com

Thanks
By:
Gyan Jyoti