LG, which currently offers both curved and non-curved 55-inch screens, is estimated to have only sold a few hundred screens so far after starting sales earlier this year.
LCD technology is also getting better and this is where many of Samsung's and LG's rivals, which lack their South Korean rivals' deep pockets, are concentrating their efforts.
"OLED demand is likely to pick up strongly only after 2015. It has a long way to go to improve picture quality to the level of ultra-high definition and to lower production costs sharply," said Chung Won-suk, an analyst at HI Investment & Securities.
Samsung, seeking to avoid putting all its eggs in one basket, also unveiled on Thursday 55-inch and 65-inch ultra-high definition (UHD) TV sets which offer crisper LCD picture resolution. Sony and Chinese manufacturers are aggressively marketing that technology.
As market dynamics remain uncertain, manufacturers' investment plans have so far been modest.
LG Display, which is also working from a pilot line, has just started investing 706 billion won ($662 million) this year in large OLED panels. Samsung Display has yet to announce its capital investment plan for production of large OLED screens.
Samsung said it will begin selling its curved OLED televisions outside South Korea from July but did not specify which countries. It has no plans to offer non-curved OLED screens this year.
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