Breakthrough claimed on paper-thin video

Associated Press

BOSTON — The picture is small and it’s far from crisp, but Dutch researchers claim they’ve taken an important step in the race for a video screen with the properties of a piece of paper.

The device, described in today’s issue of the journal Nature, is fired by plastic transistors that are flexible, potentially inexpensive to make and work well enough to constantly refresh a screen to create moving images.

Since the 1970s, researchers have tried to find a way to combine the best qualities of paper — lightness, flexibility and a sharp contrast that makes it easy to see — with the refresh capabilities of video.

They’ve dreamed of newspapers that fill themselves up with the latest stories, sports scores and movie listings, reducing the need to pulp trees for paper.

A number of companies, including Cambridge-based E-Ink and a Xerox spinoff called Gyricon Media Inc., are working on related technology, but they’ve started with static images like signs and high-quality moving images are still years away.

With video, scientists have met decidedly bigger obstacles.

So far, they’ve only been able to create the high-quality active-matrix displays necessary for moving images on glass. More flexible plastic would melt under the heat of production. Also, they’ve had to use silicon transistors, which crack if overlaid on flexible material.

But what if the transistors themselves were constructed of plastic? Then, unlike silicon, they could bend, and could be made at lower temperatures, eliminating the need for glass.

A number of researchers are trying to develop plastic transistors for a variety of uses, but so far, experts say, nobody has made them work effectively enough to create such moving images.

A year ago, the researchers at Royal Philips Electronics in the Netherlands showed how plastic polymer electronics could drive a display. Still, they only managed two shades: black and white, and the arrangement lacked the sophistication to produce real moving pictures.

Now, though, they claim in the article to have crammed 4,096 of the transistors into 2-inch display, which works well enough to create video.

For now, their device is still on glass. But they insist they’ve cleared the major hurdles for putting it on a flexible surface. And the circuits produce a decent picture: 64 by 64 pixels with 256 shades of grey and the contrast of black ink on paper.

"The biggest thing we’ve accomplished here is we integrated 4,000 transistors in one device," said Edzer Huitema, one of the researchers on the project. "There are lots of groups showing beautiful single (plastic) transistors … . What we did is show a device with 4,000 that really functions."

It also refreshes at about 50 Hertz, fast enough to stream video.

Pulling that off requires "exquisite uniformity and accuracy," said Russel Wilcox, vice president at E-Ink, which is partially owned by Philips and is collaborating on other projects with it but which was not involved in the research.

The Philips group, experts say, has brought closer the day when malleable newspapers could fill up with video as well as words. Huitema it will take at least five years.

"This is really impressive work," said Wilcox. "The world is moving closer to real, electronic paper."