OLED Technology

Preview:

DESCRIPTION

Organic Light Emitting Diode or OLED An OLED is a solid state device or electronic device that typically consists of organic thin films sandwiched between two thin film conductive electrodes. When electrical current is applied, a bright light is emitted. OLED use a carbon-based designer molecule that emits light when an electric current passes through it. This is called electrophosphorescence. Even with the layered system, these systems are thin . usually less than 500 nm or about 200 times smaller than a human hair.

Citation preview

WELCOME

OLEDOrganic Light Emitting Diode

Presented By

HAREESH KM S5 EPT 12190027

INTRODUCTION

o Uses organic light emitting

diode(OLED).

o Emerging Technology for displays in

devices.

o Main principle behind OLED

technology is electroluminescence.

o Offers brighter, thinner, high

contrast, flexible displays.

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.

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.

What is an OLED ?

• OLED - Organic Light Emitting Diode

• An OLED is an electronic device made by placing a series of organic thin films between two conductors. When electrical current is applied, a bright light is emitted.

• A device that is 100 to 500 nanometers thick or about 200 times smaller than a human hair.

.

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.

FEATURES

Flexibility.

Emissive Technology.

Light weight and thin.

Low power consumption.

High contrast, brighter and perfect display from

all angles.

OLED STRUCTURE

Architecture of OLEDs 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:

Conducting layer - This layer is made of organic plastic molecules that transport "holes" from the anode. One conducting polymer used in OLEDs is polyaniline.

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.

Working Principle(figure)

WORKING PRINCIPLEo A voltage is applied across the anode and

cathode.

o Current flows from cathode to anode through

the organic layers.

o Electrons flow to emissive layer from the

cathode.

o Electrons are removed from conductive layer

leaving holes.

o Holes jump into emissive layer .

o Electron and hole combine and light emitted.

Sample Demonstration of OLED Device

Types of OLEDs

Passive-matrix OLED Active-matrix OLED

Top-emitting OLED

Transparent OLED

Foldable OLED

White OLED

Passive-Matrix OLED (PMOLED)

Passive-Matrix OLED (PMOLED)

PMOLEDs are easy to make, but they consume more power than other types of OLED, mainly due to the power needed for the external circuitry.

PMOLEDs are most efficient for text and icons and are best suited for small screens (2- to 3-inch diagonal) such as those you find in cell phones, PDAs and MP3 players.

Active-Matrix OLED (AMOLED)

AMOLEDs consume less power than PMOLEDs because the TFT array requires less power than external circuitry, so they are efficient for large displays.

AMOLEDs also have faster refresh rates suitable for video.

The best uses for AMOLEDs are computer monitors, large-screen TVs and electronic signs or billboards

Active-Matrix OLED (AMOLED)

Transparent OLED (TOLED)

Transparent OLED (TOLED)

When turned off, are up to 85 percent as transparent as their substrate.

When it is turned on, it allows light to pass in both directions.

They are either active- or passive-matrix. This technology can be used for heads-up displays.

Foldable OLED (FOLED) Foldable OLEDs have

substrates made of very flexible metallic foils or plastics.

Potentially, foldable OLED displays can be attached to fabrics to create "smart" clothing.

White OLED (WOLED)

White OLEDs emit white light that is brighter, more uniform and more energy efficient than that emitted by fluorescent lights.

White OLEDs also have the true-color qualities of incandescent lighting.

Because OLEDs can be made in large sheets, they can replace fluorescent lights

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

PROBLEMS WITH OLED

OLED seem to be the perfect technology for all types of displays, but they also have some problems:•Lifetime:- While red and green OLED films have long lifetimes (10000 to 40000 hours), blue organics currently have much shorter lifetimes (only about 10000 hours).•Manufacturing :- Manufacturing processes are expensive right now.•Water:- Water can easily damage OLEDs

Applications of OLEDs

TVs Cell Phone screens

Computer Screens Keyboards (Optimus Maximus)

Lights Portable Divice displays

FUTURE USES FOR OLED

Lighting• 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

• 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.

Recommended