Perspective: The inventor's life

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houses a vibrating membrane, then converts the signals into ultrasonic waves. Turned to a particular point in a room--a chair, a couch, a window--the panlike object makes it seem as if the sound is emanating from that spot. If it isn't pointed in your direction, you won't hear the sound.

Sanitation companies are examining whether HSS can be deployed so that only people directly behind garbage trucks hear the annoying "ee ee ee" sound when the trucks back up.

"Imagine you're walking by a Coke machine," he says, pointing a prototype crepe pan at my head and hitting a little button. Suddenly, the fizzy sound of coke pouring over ice surrounds me.

McDonald's has installed HSS systems in select restaurants to see if they can help boost sales. ("There's a restaurant at the Aerospace Museum that does $1 million a day," Norris exclaims.). A couple of Las Vegas shows employ the system to throw sound into the audience. Trash collection companies are examining whether HSS can be deployed so that only people directly behind garbage trucks hear the annoying "ee ee ee" warning sound when the trucks back up.

HSS systems, which have been under development at ATC for nine years, sport a number of advantages over regular speakers, Norris claimed. For one thing, the sound can be directed fairly precisely. Hence, if your spouse is sleeping, the sound from the television can be directly pointed at you in HSS-enabled TV. Your husband or wife won't hear a thing.

Ultrasonic waves also don't degrade as fast. Someone 100 feet away will hear the same thing, at the same volume, that you hear while standing right in front of the speaker.

ATC came up with a similar directional sound device for the military after the U.S.S. Cole incident in 1998, when a suicide boat crashed into a navy vessel. For ship-to-ship communications, he said, "it can go for a mile over water." The company also touts HSS as suitable for "portable 'bull horn' type devices for communicating with a specific person in a crowd." New York and other cities have adopted the technology for crowd control.

"It's great for clearing birds off runways," he said. "You play the sound of their main predator. They don't get used to that one."

True to the backyard ethos of invention, HSS didn't emerge from a blinding insight during a three-day think tank.

"I got the idea while watching TV," he said. "A TV has three dots--red, green and blue--and it makes pictures by mixing light waves. So I thought, 'what else could you mix?'"

For further reading

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Ecology Coatings has developed compounds that can dry in three seconds under ultraviolet light, drastically reducing the time and space needed for painting. Not bad for a three-person company.

Biography
Michael Kanellos is editor at large at CNET News.com, where he covers hardware, research and development, start-ups and the tech industry overseas. He has worked as an attorney, travel writer and sidewalk hawker for a time share resort, among other occupations.

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