A spaceship commander asks IEEE for a status update from his pilot as they gaze at a transparent, dome-shaped navigational display. In it they see a three-dimensional model of the ship and its orientation in space as it speeds toward the mysterious planet Altair IV and a fateful rendezvous with the demented Dr. Morbius.

This scene, from the 1956 film Forbidden Planet, features a primitive wood, metal, and plastic incarnation of what has become a cinematic sci-fi archetype—3-D displays that let you see things much as you do in the real world, only in miniature, typically. The hyperrealistic 3-D display, whether it appears as the holodeck recreational environment in "Star Trek" or as the flickering holographic SOS sent by Princess Leia via R2D2 in Star Wars, underscores not only some sort of fundamental human longing but also a common assumption about high-end 3-D displays: they're way out in the future.

They're not. For decades we've had less-than-scintillating experiences watching monster movies through flimsy red-and-blue glasses and playing video games in wraparound headache-inducing goggles. Now, volumetric displays are finally here—displays that render images in a 3-D space rather than on a flat screen. But unless you're in the military, wrestle with high-end 3-D scientific visualizations, or are given to spending US $40 000 on impressive high-tech gadgets, you've probably never seen one.

A few small companies are just now emerging to try to carve out a piece of a market for volumetric displays that could be worth $1 billion by 2006, according to a study commissioned by my company, LightSpace Technologies Inc., Norwalk, Conn. These companies are pursuing two main technological approaches to displaying solid images electronically.

One is known as swept volume; it uses a high-definition projector or an array of lasers to bounce images off a screen that rotates so fast that the human eye perceives only a 3-D image floating in space. Among those pursuing the swept-volume approach are Felix 3D-Display, in Stade, Germany; Genex Technologies Inc., in Kensington, Md.; and Actuality Systems, in Burlington, Mass. (whose hemispherical displays bear an uncanny similarity to Forbidden Planet's navigation dome). The other approach, taken by LightSpace, is an all solid-state design that uses a projector behind a stack of 20 liquid-crystal screens to create one solid image from a rapidly projected series of images.

All of these systems create 3-D images that require no special eyewear, produce no eye fatigue or headaches, and are visible over a wide field of view from several meters away by many people. The first buyers are expected to put them to use in scientific, engineering, medical, and security chores, but eventually they are likely to wind up in classrooms and living rooms (adding a whole new dimension, literally, to electronic games). But for now, manufacturers are focusing on technical applications that can justify the machines' initially high prices. That means volumetric displays will first be used to help people engaged in high-stakes endeavors—a doctor guiding a catheter inside a beating heart, a geologist developing plans to extract oil from deep underground reservoirs, or a baggage screener looking for knives and bombs in carry-on luggage.

If all goes well, economies of scale could bring prices down to a point where all sorts of intriguing applications become possible. Real estate agents could give people realistic walk-throughs of properties anywhere on the planet. Fashion designers tweaking the lines of new evening gowns could see how variations hang on virtual models. Serious gamers armed with souped-up 3-D graphics cards could boost cars and splatter zombies in addictively absorbing environments that would make 3-D games played on 2-D monitors seem like creaky old cartoons.