An Ultra-High-Definition 3-D TV

Samsung has shown off a prototype of an ultra-high-definition 3-D television. The 70-inch prototype uses a novel electronic circuitry to control eight billion pixels. It's not likely to go into volume production soon, and there isn't any content to display on it, says Paul Semenza, a senior analyst at Display Search. But at last month's Society for Information Display conference in Los Angeles, the display drew crowds and garnered a best-in-show award.

Samsung is the latest TV manufacturer to demonstrate a technology that uses a type of backplane—the array of transistors used to switch the pixels on and off—based on metal oxide semiconductors. These materials offer higher performance than the amorphous silicon widely used today, without increasing costs. In April, manufacturer Sharp announced it will begin manufacturing displays based on metal oxide transistor arrays by the end of the year at its plant in Kameyana, Japan.

It wouldn't have been possible to make the ultra-high-definition display using a conventional backplane, says Sangheon Kenneth Koo, director of LCD marketing at Samsung Semiconductor. That's because making the pixels smaller requires making each of the controlling transistors smaller, too. And the amorphous silicon used in conventional backplanes doesn't conduct electrons fast enough for this kind of miniaturization.

Metal oxide semiconductors conduct electrons very rapidly, and they can be deposited using relatively inexpensive methods. The hurdle has been figuring out which mixtures of metals to use and how exactly to work with them on today's equipment, says Randy Hoffman, a senior engineer at HP. The leading material is now a mixture of indium, gallium, and zinc called IGZO.