O RGANIC L IGHT E MITTING D IODES (OLED) By Paul Naud EE230 Fall 2011 Instructor: Claire Gu

W HAT IS AN OLED? An OLED is a LED that uses the electroluminescence of organic material to emit light instead of physical characteristics of compounds like GaAs. This allows for flexibility and high resolutions

B ASIC D ESIGN Cathode Anode

B ASIC D ESIGN Cathode Emissive Layer Conductive Layer Anode

B ASIC D ESIGN Cathode Emissive Layer Conductive Layer Anode Substrate

T YPES OF OLED

P ASSIVE M ATRIX OLED (PMOLED) Controls each individual row of a display sequentially Pixels remain off for most of the time Higher voltage required for operation

A CTIVE M ATRIX OLED (AMOLED) Controls each individual row of a display sequentially Uses a Thin-Film Transistors (TFT) array for pre-charging and constant voltage.

T HIN F ILM T RANSISTORS Special Field Effect Transistor (FET) that is developed on glass Used in display technologies

T RANSPARENT OLED All components are transparent 85% as transparent as the substrate Uses either Passive or Active Matrix OLEDs

A DVANTAGES TO OLED

Lightweight Flexibility Wider Viewing Angles Power Efficiency Future Manufacturing

D ISADVANTAGES TO OLED

Lifespan Current Manufacturing Color Degradation Outdoor Performance Water damages organic materials White Light Approximately 3x more power used then LCDs Screen Burn-In Permanent discoloration of areas caused by non- uniform use of pixels

I NTERESTING D EVELOPMENTS IN OLED T ECHNOLOGIES

EDAG Light Car Smart Windshield Heads-up Displays Military Applications

QUESTIONS?