That's Not A Telegram, It's A Hologram
One day in the future, you may be sifting through your "in" box, and there, amid the paper, you'll find a movie. It won't be a reel of film or videotape, though--just a single sheet of 8 1/2-inch-by-11-inch plastic. If you look at the sheet in a strong white light, then tip the sheet forward and backward, you'll be able to view an animated sequence of 70 or more crisp, computer-generated images to show you, for example, how to use a new tool.
The technology is called animated documents, and it's the brainchild of John Andrews and a team of researchers at Xerox Corp.'s Webster Research Center, near Rochester, N. Y. The essential technology is holography, which can record many images on one surface in such a way that each is visible only from a unique angle. That produces a realistic three-dimensional effect. Right now, the apparatus needed to make a master animated document, which can be copied photographically, takes up half a room. But with work, Andrews says, the technology could be crammed into a box small enough for office use.