New Light Shed on Photodetection : Technology: A Camarillo firm’s new energy converter could affect everything from medicine to military equipment.

During the Persian Gulf War, Americans glued to their television sets saw images of so-called “smart” bombs devastating bridges, military facilities and enemy aircraft with uncanny precision. Those bombs found their targets thanks to devices about the size of a quarter that sense light and then convert it into electrical energy.

These photodetectors, introduced more than a decade ago, are used in a wide array of applications including medical imaging, facsimile machines and telecommunications. They perform essentially the same function as photomultiplier tubes, devices that look something like light bulbs and that have been around for 50 years.

But even though silicon photodetectors are much smaller and more rugged than the old glass photomultiplier tubes, they have yet to replace the tubes completely. The reason is that silicon detectors haven’t been able to function adequately when the levels of light are very low.

Advanced Photonix Inc. in Camarillo hopes to change all that. It has created a silicon photodetector it says will work in low-light situations--a development that company officials say could have an enormous impact in a wide range of fields, including medical diagnostics, night-vision military technology and eventually consumer electronics.

“It does for photonics--the conversion of light into electricity--what the transistor did for electrical circuits,” said Advanced Photonix Chairman William R. Graham.

That might sound like hyperbole, but industry observers are only slightly more subdued in their enthusiasm.

“I think everyone is pretty excited about it,” said Heather Messenger, executive editor of Laser Focus World, a Westford, Mass.-based trade publication.

Robert Clark, editor of the trade magazine Lasers & Optronics in Morris Plains, N.J., said the market outlook for Advanced Photonix “is about as good as any company I can recall over a number of years in this business.”

Advanced Photonix’s patented photodetector technology, Clark said, is “a step that a great many people have been trying to achieve for a number of years.” A few of the 15 other companies worldwide that make silicon photodetectors are working on similar technology, he said, but so far none have replicated Advanced Photonix’s progress.

During the past few months Advanced Photonix has been selling prototypes of its new photodetectors to defense contractors including Litton Industries, medical equipment manufacturers and makers of other light-sensitive equipment.

Although Advanced Photonix is the first with its new photodetector technology, Thomas T. Lewis, the company’s president and chief executive, expects competition. In the meantime, he plans to aggressively market the product, lower manufacturing costs and establish as much patent protection as possible. But ultimately, he said, “the only way to stay ahead is to go fast in terms of continuing to advance the technology.”

For now, however, Advanced Photonix--which had a total of just $357,000 in revenues and nearly $5 million in accumulated losses from the time it was founded in 1988 through Sept. 30--will turn its attention to actually selling its new photodetector.

Lewis estimated that worldwide sales of silicon photodetectors--currently about $250 million a year--could expand by $100 million by replacing photomultipliers.

That’s the market Advanced Photonix is aiming for initially. Last March the company raised $5.64 million through an initial public stock offering. Then in September, in a step designed to move its technology from the development to the manufacturing stage, it acquired for about $1.5 million Silicon Detector Corp., a manufacturer and distributor of photodetectors in Camarillo.

Lewis projected Advanced Photonix would log about $1 million in sales in the quarter ending Dec. 31, although he expects the company to remain unprofitable.

In 1992, Lewis said, bulk orders for the new photodetectors should start coming in and he expects revenues to total more than $5 million for the year. Advanced Photonix now sells the detectors for about $2,000 apiece, compared to several hundred dollars each for photomultiplier tubes. But as the company increases production and improves its manufacturing technique, Lewis said, prices of the photodetectors will fall sharply. Ultimately, he hopes the photodetectors could be made more cheaply than photomultiplier tubes, partly because the silicon they’re made of is a common element found in sand.

In a sign of the interest the new technology has generated, defense concern Litton Industries’ Electron Devices Division last month started a joint development program with Advanced Photonix that the companies say might lead to a joint venture in night-vision military technology.

Litton is interested in Advanced Photonix photodetectors because “they are good, fast-response devices,” said Litton spokesman Robert Knapp.

Possible military uses include improved night-vision equipment and guided weapons systems, Lewis said. If this new generation of photodetectors had been used in the Persian Gulf War, for instance, overcast skies would have posed no hindrance to military operations, he said. Graham added that the technology might also lead to fewer casualties due to friendly fire because vehicles could contain devices that sense when lasers are being aimed at them.

As part of its development program, Litton plans to produce demonstration units using Advanced Photonix technology for the $8.25 billion U.S. supercollider project. Litton is one of several contractors working on the federally funded supercollider project, which is aimed at exploring the origin and nature of matter by causing protons to collide at high speeds in a 54-mile, oval-shaped tunnel. The units would allow scientists to “see” the light energy that is given off when the protons crash into each other.

What’s so different about Advanced Photonix’s photodetectors?

In the simplest terms, the devices seem to solve the problem of housing in one small, durable unit the ability to sense extremely low levels of light--which might even appear as total darkness to the human eye--and convert that light into a big electrical signal. That conversion process is known as avalanche technology because it’s like a snowball rolling into an avalanche, but this technology has never been used in silicon photodetectors, industry experts say.

The new technology not only means that silicon photodetectors can replace the bulkier, more fragile photomultiplier tubes, Lewis said, but it also “allows people to consider new, unique solutions to problems that could never even be considered before.”

Using these photodetectors, for instance, detailed topographical maps of the ocean floor could be developed, or even pictures of specific objects at the bottom of the ocean, Lewis said. Medical imaging equipment such as CAT scanners and PET scanners that take “pictures” of internal organs and functions might be vastly improved, Graham said, so that many diseases could be discovered at a much earlier stage.

One day, the new silicon photodetectors might also impact the world of consumer electronics, Lewis said. Film and video cameras, for example, would possibly be able to record images in near-dark conditions.

This technology--and Advanced Photonix--was conceived thanks to two USC scientists, Gerald Huth and Andrzej Dabrowski. In 1985 the pair started Xsirius Inc., a Marina del Rey research laboratory that identifies and develops technological advances and spins off companies to market those technologies.

In addition to Advanced Photonix, Xsirius has given birth to Xsirius Superconductivity, an Arlington, Va., company involved in high-temperature superconductivity research.

In 1988 Xsirius founded Advanced Photonix and brought in professional management to run the company. Graham, a former science adviser to Presidents Reagan and Bush, is also Xsirius chairman. Lewis was recruited from his post as general manager of Lytel Inc., a fiber optics manufacturer. Xsirius currently owns 40% of Advanced Photonix’s over-the-counter stock and has options to purchase up to 52%. The stock has traded at about $5 a share for the past several months.