SEOUL (Reuters) - South Korean display screen maker Samsung SDI Co said on Thursday it had developed a 31-inch ultra-thin organic screen, raising the stakes in an accelerating worldwide race for organic displays.

Samsung SDI's announcement comes after Sony Corp began sales of 11-inch OLED TVs in November. The Japanese company has showcased a 27-inch prototype OLED TV in the past.

Flat screen makers are increasingly looking at active-matrix organic light-emitting diode (AM-OLED) as a growth driver because they produce brighter images and use less power.

Samsung SDI officials declined to say when the company's 31-inch OLED screen would be mass-produced, saying the decision depended on TV set makers' plans.

But they said Samsung Electronics , the world's largest maker of liquid crystal display (LCD) TVs, would showcase a 31-inch prototype TV set at the Consumer Electronics Show in Las Vegas in early January.

Samsung SDI is also planning to mass-produce 14-inch screens in 2008, Yoo Eui-jin, head of Samsung SDI's AM-OLED team, said at a press conference introducing the display.

Although Yoo declined to name the companies that would use the AM-OLED screens, he said a number of companies had expressed interest.

Samsung SDI said its 31-inch module is only 4.3 mm thick, or one-tenth of a typical liquid crystal display panel, and consumed less than half the electricity needed for a 32-inch LCD screen.

Samsung SDI also said the lifespan of its display was 35,000 hours, the best performance among existing AM-OLEDs.

While small AM-OLED displays are already in use on premium mobile phones and media players, large-sized models are particularly difficult and costly to make. Shipments of Sony's 11-inch OLED TVs have been limited to 2,000 units per month.

Earlier this month, Japan's Toshiba Corp said it had shelved plans to sell AM-OLED TVs in 2009-10 because of the cost of mass production.

(Reporting by Marie-France Han; Editing by Sei Chong)

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