At a time when the screen size of television sets is growing so fast that it appears headed to eclipse that of movie theater screens, the latest breakthrough in display technology has come in the form of an ultraslim 11-inch (28-centimeter) screen that is a mere 0.12 inch (three millimeters) thick at its thinnest point.

The innovation in Sony's new XEL-1 television is its use of organic light-emitting diode (OLED) technology that promises advanced levels of contrast and brightness, a broad spectrum of color reproduction and a rapid video response rate. OLED technology is also touted for its environmental friendliness.

Sony plans to introduce the XEL-1 television in December exclusively to the Japanese market at a cost of 200,000 yen (around $1,700) per unit. The company has not announced plans to offer an OLED TV in North America, although it is considering marketing it outside of Japan, a Sony spokesman says. He adds that Sony is "actively working on larger OLED screen sizes."

Whereas a liquid-crystal display (LCD) removes light from a backplane to create its picture, an OLED emits light, which creates "a rather substantial amount of efficiency," says Stephen Forrest, a University of Michigan at Ann Arbor vice president for research and a professor of electrical engineering and computer science. Since OLED pixels only consume energy when they're in use, they can consume up to 40 percent less energy than LCDs. "LCD screens also have polarizers (applied to the LCD glass plate)," he says, "that make viewing very angle dependent. OLEDs don't have all of the viewing angle deficiencies."

OLEDs also make it possible for manufacturers to incorporate some fun novelties into their products. For instance, OLED panels could be made to show images on both sides, and they can be clear when they are turned off.

"The displays that Sony is making are really quite beautiful," says Mark Thompson, chairman of the University of Southern California's chemistry department, who has studied the use of organic molecules to create an organic LED. "It's a shame they're only 11 inches."

There are several obstacles to making larger OLED displays. The most glaring: in an OLED TV, there is a transistor backplane that controls the brightness of each pixel. "You need millions and millions of these transistors—with very few failures—to make this work," Thompson says. In order for an OLED to be more energy efficient and produce a clearer picture than an LCD screen, there needs to be a way to deposit red, green and blue pixels where each transistor is positioned. This challenge grows exponentially as the screen size grows.

Sony has demonstrated a 27-inch OLED prototype display, but the screen actually consists of four individual displays arranged to produce a single image, Thompson says. This sets up an additional hurdle, because the colors are difficult to match from one display to the next.

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