OLED
TECHNOLOGY
Introduction
• Uses 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 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.
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.
• OMany 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
• 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.
Structure of Oled (Figure)
•.
Oled Fabrication
• Substrate preparation.
• Device deposition
★ Deposit and pattern anode.
★ Pattern organic layers.
★ Vacuum deposit and pattern cathode,
• Encapsulation.
• Also involves making backplane.
Oled Deposition
• Organic layers can be applied to the using the
following methods.
•
— Evaporation and shadow masking
•
— Inkjet printing
•
— Organic vapour phase deposition
Evaporation and Shadow
Masking
Inkjet Printing
Organic Vapour Phase
Depostion
Colour Generation
• Differnt 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
Types of Oled
• Six types of OLEDs :• Passive matrix OLED(PMOLED).
• Active matrix OLED(AMOLED).
• Transparent OLED(TOLED).
• Top emitting OLED.
• Flexible OLED(FOLED).
• White OLED(WOLED).
Passive Matrix Oled
Active Matrix oled
Transparent Oled
Top Emitting Oled
Flexible Oled
White 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.
Oled Diadvantages
• Expensive
• Lifespan
• Water damage
• Color balance issues.
Oled Vs . Lcd
• OLED
• Greater view angle
• High contrast
• Faster response time
• Do not require
backlighting .
• Temperature (50°C —
80°C).
• LCD
• Limited view angle.
• Low contrast
• Slow response time.
• Require backlighting.
• Temperature (0°C—
100°C)
Applications
• Major applications of oled technology
• OLED TV
• Mobilephones with OLED screens.
• Rolltop Laptop
Oled TV
Mobile Phones with oled
screen
Rolltop Laptop
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.
Thank you