Susan Kasen Summer was not satisfied with the three-dimensional graphics software being developed for personal computers. Although the software depicts 3-D objects, the effect suffers because the images appear on a flat screen. Three years ago Summer formed her own company, Dimensional Media Associates in New York City, to develop a technology to make 3-D images that truly stand out.
The result is her high-definition volumetric display, or hdvd. It is essentially a booth with a 40-inch-wide pane of glass with some fancy optics behind it. The optics create the illusion of a three-dimensional object suspended in the air a few feet in front of the screen. The images appear so real that they defy the brain’s ability to perceive them as virtual, says Summer.
The optics--a system of mirrors, beam splitters, lenses, and so on--do basically what a hologram does, except that the light that reaches the eye is not reflected off a flat surface but rather is projected from behind the booth. Unlike a fixed hologram, the optics allow Summer to project moving images. For instance, she can take a two-dimensional motion picture image--say, of a fashion model walking a catwalk--and project it out into free space. Then, using such tricks as bending the image slightly and projecting a separate background, she can make the image appear to take on a solid three-dimensional form.
Although it sounds like science fiction, the applications are strictly down-to-earth. Summer is now marketing the device to jewelry retailers who want to make their watches and necklaces appear to float in thin air over the sidewalk in front of their stores and to advertisers who want to make 3-D billboards. A similar product still in the works will project 3-D images in front of movie screens, and another will create 3-D images of human organs for surgeons in training.
Advanced Laser Technologies’ Thinline Display
Innovator: Don Conemac
Seven years ago, while he was unemployed and in the midst of an acrimonious divorce settlement, Don Conemac sought inspiration. I prayed that the Lord might allow me to conceive an idea to help me keep my son, he recalls. In short, he needed a way to make a living. As he lay on his bed and joined his hands in prayer, his left elbow accidentally hit a wire connected to the cylindrical laser he had been working on earlier. As the laser rolled off a table, its beam happened to strike a fluted, shiny knob on his stereo, which reflected it onto the wall. As Conemac glanced at the moving dots of color, he realized that a laser beam moving across a rotating mirror could form the basis of an entirely new type of television or computer display.
By 1995, Conemac, an electrical engineer, had succeeded in turning his vision into a prototype of the Thinline display. It works this way: Several red, green, and blue laser beams are shone onto a spinning wheel on which 36 tiny mirrors are mounted. The mirrors redirect the beams to an array of optical fibers, which carry the beams onto a transparent polymer screen. The Thinline display has none of the phosphors or other light-emitting materials that conventional television and computer screens use to produce the image. What’s really neat, explains Conemac, is that each point of light is the pure energy of the laser.
The biggest advantage of Conemac’s technology is that it allowed him to make his display very thin indeed: even though the screen can be made as big as 120 inches diagonally, it is only 5 inches thick. Building a slender, full-color, high-resolution video display screen has been one of the holy grails of technology.
Conemac believes Thinline will also catch on as a wall board for classrooms, as a display screen for advertising, and as an instrument panel for cars. The screen could be made portable and foldable, as well as interactive, by placing simple light detectors behind it to measure small changes in contrast when people touch it.
In 1993 Conemac and his collaborators founded Advanced Laser Technologies in Moorpark, California. They expect to have the display ready for market later this year. Ultimately, by using a new, ultrasensitive polymer as the screen, Conemac plans to reduce the thickness of the display to just one inch.
TV’s a Gas
Sony/Technical Visions/Tektronix’s Plasmatron Video Display
INNOVATOR: THOMAS BUZAK
Sometimes boredom is the mother of invention. It was for Thomas Buzak. When a project he was working on at the electronics firm Tektronix in Beaverton, Oregon, was canceled a few years ago, the electrical engineer began casting around for something else to do. Buzak got the idea for a new way of making a flat-panel display to replace the bulky cathode-ray tube-- the same holy-grail challenge that Discover Awards finalist Don Conemac tackled.
Buzak’s invention combines the best of two technologies for flat- panel displays. So-called active-matrix displays, which use millions of tiny transistors, each controlling one point on the screen, produce high- quality images but don’t scale up well for screens larger than 15 inches. Plasma displays can be large, but they are hard to see in a well-lit room. Buzak replaced the millions of transistors in the active-matrix display with what he calls plasma switches that do the same thing conventional transistors do--turn on points of the screen to form an image--but are simpler to manufacture and can be scaled up to large sizes.
The screen consists of three layers. On the bottom are rows of tiny grooves that run left to right. Each groove is filled with a gas that when activated by an electric signal turns into a plasma--an ionized gas that conducts electricity. The top layer is a series of electrical wires running up and down. Sandwiched between this grid is a layer of liquid crystals, similar to the ones in a watch or a laptop computer display, which turn from dark to light in the presence of electricity. To lighten any one point of the screen, an electric signal is sent through a vertical wire while a row of plasma is activated. Since the plasma conducts electricity, an electric field is created between it and the wire, causing the liquid crystals to let light pass through that point on the screen. To get different colors, Buzak simply uses separate green, red, and blue filters on the liquid crystals. The plasma is gaseous electronics, explains Buzak. The liquid crystal is the actual image generator that you look at in the display.
The resulting image, says Buzak, is just as good as that of conventional active-matrix technology. Buzak began developing the display, called the Plasmatron, while at Tektronix and then left to form his own company, Technical Visions, also in Beaverton. Since 1992 Tektronix and Technical Visions have been working with Sony to bring a wall-hanging television to market. The fruits of the three companies’ labor will pay off this fall, when Sony will introduce the Plasmatron first in Japan and then later in the United States.
Matsushita’s Digital Camcorder
Innovator: Mikio Higashi
When it comes to audio products, the digital format of compact discs has come close to replacing the old-fashioned analog format of lp records. Mikio Higashi and his colleagues at Matsushita Electric Industrial Company in Osaka, Japan, have suspected for years that that may become true for video too. After all, professional broadcasters rely on digital technology to achieve their impressive special effects. The problem that Higashi faced, of course, was how to make such expensive technology available to the masses.
After ten years of development--not to mention haggling between the big electronics companies over technical standards for digital video-- last year Higashi’s team unveiled the Panasonic pv-dv 1000, a digital camcorder designed for home use. Like the professional versions, rather than using film to capture the images, it has three charge-coupled devices, or ccds, light-sensitive computer memory chips--one each for red, green, and blue. The difference is that Higashi’s engineers managed to reduce the complex electronics needed for manipulating digital video signals into a package of unprecedented compactness. To cut down on the amount of computer memory they needed, they devised a scheme for compressing the signals needed to describe a video image. They also invented a magnetic tape that can pack video signals more densely than conventional tape. These and other innovations helped reduce the cost and increase the reliability of the product.
The result indeed does for video what the cd player did for audio. For one thing, the image quality is better because each image is composed of about 500 horizontal lines, compared with only about 240 for conventional analog videocassette recorders. And since the digital format is so compact, the cassettes can hold an hour of video even though they are one-twelfth the size of vhs cassettes and only slightly larger than microcassette tape recorders. In the future, Higashi believes, he and his colleagues will be able to cram the electronics into a much smaller, cheaper package. Digital video, he says, is very suitable for the multimedia age.