Japan's consumer electronics companies are investing billions of dollars in flat-panel TVs, but a dispute is raging over which is the best technology to use for the very largest screens.
Most vendors seem to agree that liquid crystal displays (LCDs) are best for TV screens up to 37 inches in diagonal. But for larger screens they disagree about whether LCDs or a plasma technology called Plasma Display Panel (PDP) is best suited for the task.
The battle pits Matsushita Electric Industrial, better known by its Panasonic brand, and Pioneer, which are backing plasma, against Sharp, which is promoting LCDs. Sony seems to have a foot in both camps.
Complicating the matter, a new technology called Surface-conduction Electron-emitter Displays (SED) is emerging on the scene. Canon and Toshiba claim the picture quality of SED will eventually make it the best choice of all.
With consumers cramming ever larger TVs into their living rooms, the stakes for manufacturers are high. Worldwide, sales of TVs with screens greater than 40-inches are expected to triple in the next few years, from about 7.2 million in 2004 to 22 million in 2008, according to market research company, iSuppli.
Proponents of plasma argue that very large LCD screens are too costly to produce and run into problems with picture performance.
"When you look at a very dark scene on an LCD you can see it doesn't do so well," a PDP product planner at Pioneer, Daijiro Sato, said.
Matsushita, which invested $US865 million in a new PDP plant earlier this year, says pictures can show blurring on LCD screens larger than 37-inches. It also thinks the viewing angle is too small, meaning the picture is not clear when the screens are viewed from the side.
"LCD was originally developed for PCs, for people who are always facing a computer screen," manager of Matsushita's PDP development team, Mitsuhiro Kasahara, said.
He also argued that LCD yields - the proportion of good screens from a given quantity produced - will decline as they increase in size. "LCDs are difficult to make," he said.
Not surprisingly, Sharp dismisses these arguments. The picture quality of its LCD TVs is beyond question, it says. Its newer screens have a viewing angle of 170 degrees and achieve a contrast ratio of 800:1, allowing them to show deep black tones even in direct sunlight, Sharp spokeswoman, Miyuki Nakayama, said.
"A few years ago, PDPs over 40-inches were said to suit the flat TV market, but this myth has changed completely," she said. And the screens will only get bigger: Next year Sharp plans to release an LCD TV with a screen greater than 50-inches across, which it hopes to price competitively with plasma TVs of about the same size.
Sony is another backer of LCDs. In April it partnered with Samsung to set up a joint venture company, S-LCD, which should begin panel production next year.
It would emphasise LCD as its core TV technology, President Kunitake Ando said last month. S-LCD could be making three million 40-inch panels within a few years of starting production, he said.
But Sony is, in fact, backing both LCD and plasma. In August it unveiled its latest TVs, headed by a top-of the-range Qualia model, with a 46-inch LCD screen. But three of its new sets - 37-inch, 42-inch and 50-inch models - have plasma screens.
President of Sony's TV group, Makoto Kogure,, said that plasma had cost advantages over LCD at the high end, but that LCDs were superior for smaller TVs because they could support higher resolutions more easily.
The argument that plasma displays were cheaper to produce was partially true, but that should change as LCD makers became more efficient at production, a senior analyst at iSuppli, Riddhi Patel, said.
Prices vary widely, but in general, for TVs 40-inches and above, prices for LCD models tend to be two to three times as high as those for plasma. But LCD prices have been falling sharply and could be on a par with those of plasma by 2008, according to iSuppli.
"It's a question of how efficiently LCD producers can make 40-inch and larger sizes. But as it will take time to improve yields (for LCD screens), plasma has the near-term advantage," Patel saidw.
And plasma may also have the brighter future. Worldwide sales of PDP TVs over than 40-inches should hit 1.9 million this year, double the figure from 2003, and climb to 11 million units in 2008. Sales of LCD TVs of the same size, on the other hand, will rise from just several hundred thousand in 2005 to about 3.5 million in 2008, according to iSuppli's predictions
And so what of the dark horse, SED?
Its backers claim that SED offers a superior picture with just half to one-third of the power consumed by plasma or LCDs. The technology combines cathode ray tube (CRT) and LCD technologies. As with CRTs, electrons hit a phosphor-coated screen to emit light, but instead of being shot out of a gun, they are drawn out of an emitter through tiny slits. At the recent Ceatec show near Tokyo, lines formed each day to watch the new technology in action.