Non-Intrusive Inspection (NII) imaging systems — or industrial x-ray imaging systems — are used by U.S. Customs and Border Protection (CBP) officers and port operators to inspect air, land, and sea cargo for contraband, including weapons, narcotics, explosives and potentially nuclear and radiological threat materials.

Recent technological advances, funded through the Domestic Nuclear Detection Office (DNDO)'s Small Business Innovative Research program, have led to the next generation of technology used to produce the x-rays in these NII systems, facilitating faster scanning and more precise material discrimination for mobile operations.

The Technology

The x-ray generator features a source of high-energy electrons that are used to produce a spectrum of x-rays. This innovative and revolutionary x-ray source, called a linear accelerator, is more compact and has more capabilities than current x-ray sources, which include:

• The capability to produce high pulse rates up to 1000 pulses of x-rays per second
• The capability to produce multiple x-ray energies ranging from 2 MeV to 9 MeV
• The capability to change the intensity of the x-rays from pulse-to-pulse

The high pulse rate enables faster and more efficient scanning of cargo, while the multiple x-ray energies facilitate material discrimination and detection of contraband. Depending on the density of the cargo being scanned, the intensity variation capability enables systems to easily increase or decrease the amount of x-rays being generated. Additionally, the compact size facilitates mobile applications with a reduced operational footprint.

Current Status

This compact, multi-energy x-ray generator has caught the attention of commercial vendors of NII systems and will soon become integrated in their systems. One vendor is already using a variant of this generator in its latest generation scanning solution. This integrated system provides multi-energy imaging performance in a bus-mounted platform.