Oled organic

WELCOME

OLEDOrganic Light Emitting Diode

Subin JamesS7EE

Pressented by

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.

.

History of OLEDs

• First developed in the early 1950s in France

• Early technology would emmite a short burst of light when a voltage was applied

• This early form applied high-voltage alternating current field to crystalline thin films of acridine orange and quinacrine.

• 1960s - AC-driven electroluminescent cells using doped anthracene was developed.

• In 1987 Chin Tang and Van Slyke introduced the first light emitting diodes from thin organic layers. 

• In 1990 electroluminescence in polymers was discovered. 

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.

• Organic layer: o Conducting layer - This layer is made

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

o 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.

  • Cathode (may or may not be transparent depending on the type of OLED) - The cathode injects electrons when a current flows through the device.

How OLEDs Emit Light ?

• The battery or power supply of the device containing the OLED applies a voltage across the OLED.

• An electrical current flows from the cathode to the anode through the organic layers. (an electrical current is a flow of electrons

• At the boundary between the emissive and the conductive layers, electrons find electron holes.

• The OLED emits light.

Types of OLEDsPassive OLEDs• The organic layer is between

strips of cathode and anode that run perpendicular

• The intersections form the pixels•  Easy to make• Use more power• Best for small screens

Active OLEDs• Full layers of cathode and

anode•  Anode over lays a thin film

transistor (TFT)• Requires less power• Higher refresh rates• Suitable for large screens

TOLED• It is the property of top contact ,it

is optically transparent or a reflective metal

• Transparent substrate, cathode and anode

• TOLED uses a transparent contact to create a display(both top and bottom contacts allow light transmission)

• Bi-direction light emission.• TOLEDs can greatly improve

contrast. i.e. good daylight visibility

(because it is 70% trnasparent when turned off).

Fig : power efficiency and luminance of oled as a function of current density.

To increase power efficiency

• Operating voltage and current density of OLED

• Reducing the distance between solar cell and OLED

• Increasing the panel size(Large area)

Applications of OLEDs

• TVs• Cell Phone screens • Computer Screens• Keyboards (Optimus Maximus)• Lights• Portable Divice displays

OLED Televisions

• Released XEL-1 in February 2009. • First OLED TV sold in stores.• 11'' screen, 3mm thin• $2,500 marcket price• Weighs approximately 1.9 kg • Wide 178 degree viewing angle• 1,000,000:1 Contrast ratio

Sony

Optimus Maximus Keyboard

• Small OLED screen on every key• 113 OLED screens total• Each key can be programmed to

preform a series of functions • Keys can be linked to applications• SD card slot for storing settings

OLEDs as a Light Source

Advantages of OLEDs

• 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

OLED Displays Vs. LCD and Plasma

OLED Lighting Vs. Incandescent and Fluorescent  • Cheaper way to create flexible lighting• Requires less power • Better quality of light • New design concepts for interior lighting

Disadvantages of OLEDs

OLED Displays Vs. LCD and Plasma• Cost to manufacture is high• Overall luminance degradation• Constraints with lifespan • Easily damaged by water• Limited market availability

  •  Lifetime

• White, Red, Green 46,000 hours , Blue 14,000 hours

 OLED Lighting Vs. Incandescent and Fluorescent • Not as easy as changing a light bulb

Future Uses for OLEDLighting• Flexible / bendable lighting• Wallpaper lighting defining new ways to light a space• Transparent lighting doubles as a window • Heads up display.

 Cell Phones• Nokia 888

References• http://impnerd.com/the-history-and-future-of-oled• http://en.wikipedia.org/wiki/Organic_light-emitting_diode• http://www.oled-research.com/oleds/oleds-history.html• http://www.voidspace.org.uk/technology/

top_ten_phone_techs.shtml#keep-your-eye-on-flexible-displays-coming-soon

• http://www.pocket-lint.com/news/news.phtml/23150/24174/samsung-say-oled-not-ready.phtml

• http://www.cepro.com/article/study_future_bright_for_oled_lighting_market/

• http://www.technologyreview.com/energy/21116/page1/ • http://optics.org/cws/article/industry/37032 • http://jalopnik.com/5154953/samsung-transparent-oled-display-

pitched-as-automotive-hud

THANKS