Holographic imaging scans for trouble - Security

USA Today (Society for the Advancement of Education), April, 2003

A holographic imaging system that is designed to identify rapidly hidden weapons, explosives, and other contraband--even plastic, ceramic, and other nonmetallic weapons--through clothing is the cornerstone of an effort to commercialize the technology for a variety of security applications. Using millimeter waves to generate holographic images, it was developed by the Department of Energy's Pacific Northwest National Laboratory, Richland, Wash., for the Federal Aviation Administration to scan airline passengers as they pass through airport security checkpoints.

The holographic imaging system is distinctly different from current surveillance systems that rely on metal detectors, X-ray imaging, and, in some cases, strip searches. Metal detectors cannot screen for plastic or ceramic weapons, plastic explosives, or other types of nonmetallic contraband, while X-ray imaging subjects people to potentially harmful ionizing radiation.

"We believe that the imaging system has enormous potential for use in screening people at points of entry to mass transit systems, including airports, subways, and trains; border crossings; government installations such as courtrooms, military bases, prisons, embassies, and office buildings; crowded public places such as sports arenas, concert halls, and museums; and commercial buildings," maintains Mike Lyons, chairman of SafeView, Menlo Park, Calif., which is helping to establish holographic imaging system product development.

"While the technology was developed to identify dangerous objects or contraband that people might bring into a facility, we believe it also could be used to protect against theft by identifying concealed items that people might try to remove from facilities, ranging from museums to nuclear plants," explains Doug McMakin, an engineer who was a principal developer of the technology.

Looking much like a conventional metal detector, the system projects ultra-high-frequency, low-powered radio waves onto the front and back of the individual being screened. These waves--known as millimeter or centimeter waves because they have wavelengths of about one centimeter--penetrate clothing and bounce off who is being screened and the items he or she may be carrying. A sensor array captures the reflected waves and sends the information to a high-speed image-processing computer, which analyzes the information and produces a high-resolution, three-dimensional image that allows an operator to screen for suspicious materials.

The security scanner has its roots in a three-dimensional holograph imagery technology program that was established at Pacific Labs in the 1970s to develop nondestructive evaluation technologies for nuclear reactors. In the mid 1980s, the FAA became interested in the technology's potential for scanning people passing through airports and began funding research.