An OLED is made by placing a series of organic thin films between two conductors. When electrical current is applied, a bright light is emitted. Here's Kodaks description of OLEDs -
"OLED displays stack up several thin layers of materials. They operate on the attraction between positively and negatively charged particles. When voltage is applied, one layer becomes negatively charged relative to another transparent layer. As energy passes from the negatively charged (cathode) layer to the other (anode) layer, it stimulates organic material between the two, which emits light visible through an outermost layer of glass."

OLEDs have the potential to make exciting TVs (or computer displays). OLED are bright, ulta-thin, low power, and they show beautiful pictures. Sony will start selling OLED TVs in December 2007. But these will be small and pricey. The main issue is the lifetime (OLED displays degrade after a certain time), and also production cost are still high (Although theoretically OLEDs may become cheaper than LCD). Sony's OLED (Organic Light Emitting Diode) TV, the XEL-1, is truly the next big thing in television technology.
The XEL-1 is an 11 inch display that is only 3mm thin. The measurements of the XEL-1 are 287×253×140mm.
Sony has put the ultra-thin display on a pedestal with a flexible arm. At 11 inch the Sony XEL-1 is a nice stylish desk accessory.
The latest OLED TV (XEL-1), which weighs two kilograms and is about 3mm thin, features a resolution of 940×540 and contrast ratio of 1,000,000:1, stated Sony.

Other good OLED Information websites:
http://hubpages.com/hub/OLED
http://www.squidoo.com/oled-tv
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