Video: And Now, Dynamic Discs

New TV technology opens a world in which touching is believing

The child's hand reaches out tentatively. Years of haranguing ("Keep your greasy fingers off the TV!") have made the screen taboo. But when the child sees that his finger causes the image to change, learns that his touch magically provokes new pictures, sequences, words and diagrams, his hand begins to jab, rub and slap the screen. Curiosity, once aroused, is satisfied by simply touching a picture of what one wants to understand. This process is re-enacted thousands of times every day at the U.S. Pavilion at Energy Expo '82 (a.k.a. the Knoxville, Tenn., World's Fair) as exuberant children and their more inhibited parents discover that TV viewing is passive no longer. The technology is called the interactive videodisc: the symbiosis of the computer and the laser-vision disc.

Clustered inside the wedge-shaped steel-and-glass pavilion are 42 TV screens connected to 42 Sony videodisc machines, which are hooked up to 23 Apple II computers. Nine video stations on the ground floor explain the meaning of 480 energy-related terms. Don't know what a Pelton wheel is? Press the word on the screen, and presto!, a swirling water turbine appears. A different set of screens shows a colorful cutaway drawing of a house. Wondering how to make your home energy-efficient? Just touch the attic, for example, and watch a demonstration of how to insulate it. According to Emmett Cunningham of the U.S. Department of Commerce, the genial director of the exhibit, "It's the best and most durable public information system I've seen in 25 years in the exposition business."

The system, says its unflappable designer, Tom Nicholson of the New York City exhibition firm of Ramirez and Woods, "personalizes" information. Determined to avoid an intimidating computer keyboard, he employed a "user-friendly," touch-sensitive screen. Pressure on the screen tells the computer to retrieve the information stored on the videodisc corresponding to the word or symbol touched. Although the computer makes the system truly responsive, what makes its applications so exciting is the versatility of the videodisc. And you thought the disc was the Edsel of video technology.

Alas, the poor videodisc, so misunderstood, so maligned. Most people think it a single-purpose instrument, a movie machine. The misconception was fostered by the much ballyhooed introduction in 1981 of RCA's Selecta Vision, 15 years and $200 million in the making. Not a truly innovative technology, Selecta Vision is essentially a phonograph that uses a mechanical stylus to play prerecorded movies. Its costly debut obscured the second type of videodisc: the infinitely more versatile laser-vision disc, designed for the videodisc player introduced by Magnavox in 1978. Manufactured by Pioneer, Sony and the 3M Co., the laser-vision disc makes flexible interaction possible.