By Reid Kanaley Knight Ridder Newspapers (KRT) PHILADELPHIA _ They do it with mirrors. Start-up company Ethereal Technologies Inc., of West Philadelphia is developing devices that make three-dimensional images appear to hover in space before the viewer’s eyes. Think of someday playing the Sims video game with the characters appearing to traipse around on a tabletop instead of on a screen. Instead of using Star Wars-like holography, Ethereal creates the illusion by projecting stereoscopic right-eye and left-eye video images onto a single concave mirror sitting several feet away from a person. The mirror, in turn, reflects those images directly at the viewer’s eyes. What happens is that the person looking toward the mirror sees a single, three-dimensional picture that seems to be suspended in the air between the person’s eyes and the mirror. The company compares the result to a laser-produced hologram _ which is what many people think of when they hear about 3D images _ but says its technology delivers pictures that are sharper than currently possible in holography. The technology _ which has taken about $1 million in government and private funds to develop _ could eventually prove useful by providing depth perception in applications such as luggage X-rays in airports and surveillance cameras where a three-dimensional image might be more revealing, as well as in medical imaging, and video gaming, a multibillion-dollar industry. Robert Andrews, 62, an optics expert who retired from Ford Motor Co.’s design center in 1997, founded Ethereal in 1999. He collaborates with researchers in England, Scotland and Ireland. Andrews, of Ann Arbor, Mich., spent several years at Ford trying to develop a way for car designers to use holograms to visualize their creations in three dimensions. Linda Yu of Newtown Square, Pa., a dot-com veteran who began her career as a systems engineer at International Business Machines Corp., is the new chief executive officer of the five-employee company. Yu, 46, was hired four months ago to chase down new markets and funding for the venture. In December, she moved into office space at the Port of Technology, a for-profit business incubator inside the University City Science Center. A handful of the first large versions of the Ethereal equipment _ the centerpiece is a 1,000-pound parabolic mirror that resembles a big-screen projection TV set and costs $50,000 _ have gone to medical and scientific researchers. For example, a Connecticut research lab is using one to view 3D images from an electron microscope, the U.S. Army is evaluating uses in surveillance and night-vision, and DaimlerChrysler Corp. auto designers have one, Yu said. But, Andrews said, one day “my youngest son, who is 14, came to my office (and) said: `Forget all this science stuff. Think video games. We’ll be millionaires.'” “So we have gone ahead and developed what you would call a desktop version,” Andrews said. “We’ll just call it a 3D monitor. It sits on your desk, about 24 inches in front of you.” He sees uses for the device in teleconferencing, education, “and just going on the Internet and doing things in 3D. There’s got to be a huge market there.” The smaller device initially would cost $2,000 to $3,000, Yu said. Andrews said he learned of Yu _ who has headed some online ventures for companies including Aetna Inc. and Discovery Communications Inc. _ from a colleague in Scotland, who told him: “There’s an American woman in Philadelphia you really ought to talk to and get on your team.” They did talk. Yu said she was interested in the job, and went on to convince Andrews that Philadelphia’s proximity to New York and Washington made it a good place to base the company. With her two children settled into Marple Newtown schools, “I didn’t want to move,” Yu said. Yu is hunting for the companies and government agencies that could see a use for Ethereal’s technology. “I have to beat the bushes,” she said. “But this (product) has immediate impact on those people it’s relevant to.” ___ ‘copy 2003, The Philadelphia Inquirer. Visit Philadelphia Online, the Inquirer’s World Wide Web site, at http://www.philly.com/ Distributed by Knight Ridder/Tribune Information Services.