At an exhibition at Makuhari Messe in Chiba in 2002, a crowd at the Sanyo Electric booth gawked as they were treated to a demonstration of a trial version of an organic electroluminescent (EL) display, the first time such a panel had ever been shown to the public.
The panel, the size of a TV set, was only 2-mm thick (half as thick as a liquid crystal display) and could be viewed clearly from the side.
Known as an “organic EL display panel,” the next-generation viewing screen has electronics makers locked in a fierce development war that threatens to stop LCD displays in their tracks.
In an organic EL display, voltage is applied to organic matter sandwiched between two sheets of glass, causing it to glow. Because the light emissions are self-generated, there is no need for the backlighting that makes liquid crystals viewable.
Theoretically, the two sheets of glass can be made to a thickness of only 1 mm.
Sanyo has succeeded in finding a practical application for organic EL displays in digital cameras, but now it wants to put them in TVs.
“We will stop producing liquid crystal if the outlook for practical (organic EL display) use is in sight, and will introduce it in all thin TV sets,” Sanyo Chairman Satoshi Iue said.
In the 1960s, it was confirmed that certain organic elements emit light when treated with an electric current, but full research into the phenomena only began in 1987.
A researcher at Eastman Kodak Co. found a light-emitting material that glowed brighter at low voltages, triggering a development race between Sanyo, Sony Corp. and Kyocera Corp.
“Whether an efficient material can be found will determine the race. We are making every effort to find such a material,” said Kenichi Shibata, director of Sanyo’s technology development headquarters.
In contrast with electronic parts, the characteristics of the organic matter itself will determine almost entirely how bright and stable the product will be, Shibata said.
There are several hundred organic elements that emit light when voltage is applied, but only a few are satisfactory for practical use. And to display pictures in full color, light emitters in three principal colors — red, blue and green — will need to be found.
Durability is another problem, especially for TVs.