by John Markoff

Intel scientists say that they have made silicon chips that can switch light like electricity, blurring the line between computing and communications and presenting a vision of the digital future that will allow computers themselves to span cities or even the entire globe.

The invention demonstrates for the first time, Intel researchers said, that ultrahigh-speed fiberoptic equipment can be produced at personal computer industry prices. As the costs of communicating between computers and chips falls, the barrier to building fundamentally new kinds of computers not limited by physical distance should become a reality, experts said.

The advance, described in a paper to be published on Thursday in the scientific journal Nature, also suggests that Intel, as the world's largest chipmaker, may be able to develop the technology to move into new telecommunications markets.

It will free computer designers to think about the systems they create in new ways, making it possible to conceive of machines that are not located in a single physical place, according to scientists and industry executives. It will also make possible a new class of computing applications based on the possibility of transmitting high-definition video and images hundreds or even thousands of times faster than possible on today's Internet.

"Before, there were two worlds -- computing and communications," said Alan Huang, a former Bell Labs physicist, who has founded the Terabit Corporation, an optical networking company in Menlo Park, Calif. "Now they will be the same and we will have powerful computers everywhere."

One potential application, he said, would be an interactive digital television system allowing viewers to watch a sporting event from multiple angles, moving the point of view at will while the game is being played. With only a limited number of digital cameras, it might be possible to synthesize a virtual moveable seat any place in the stadium. Such a feature exists currently in video games, but it is far beyond the capacity of today's digital television transmission systems.

Intel said the technical advance, in which the researchers use a component made from pure silicon to send data at speeds as much as 50 times faster than the previous switching record, is the first step toward building low-cost networks that will move data seamlessly between computers and within large computer systems.

"This opens up whole new areas for Intel," said Mario Paniccia, a an Intel physicist, who started the previously secret Intel research program to explore the possibility of using standard semiconductor parts to build optical networks. "We're trying to siliconize photonics."

The device Intel has built is the prototype of a high-speed silicon optical modulator that the company has now pushed above two billion bits per second at a lab near its headquarters in Santa Clara, Calif. The modulator makes it possible to switch off and on a tiny laser beam and direct it into an ultrathin glass fiber. Although the technical report in Nature focuses on the modulator, which is only one component of a networking system, Intel plans on demonstrating a working system transmitting a movie in high-definition television over a five-mile coil of fiberoptic cable next week at its annual Intel Developer Forum in San Francisco.

"If Intel and other semiconductor technology companies can develop silicon optically as successfully as they have electronically, then silicon is certainly set to grow in stature as an optical material," Graham Reed, a physicist at the University of Surrey, wrote in a commentary on the Intel paper in Nature. Dr. Reed is the holder of the previous 20-megabit silicon optical switching speed record that Intel shattered.

With this breakthrough, Intel researchers said, they have shown that it should be possible to build optical fiber communications systems using Intel's conventional chipmaking process without resorting to either the exotic materials or hand-assembly techniques that are now the standard in the fiberoptics networking industry.