X-ray Backscatter Security Inspection with Enhanced Depth of Effective Detection and Material Discrimination

X-ray imaging techniques based on Compton backscatter allow inspection and screening of a variety of vehicles, cargo containers, luggage, suspicious packages, aircraft and spacecraft components, as well as building walls and floors. Backscatter imaging systems are in wide use by government agencies, border authorities, law enforcement personnel, military organizations, and security services in many countries.In contrast to commonly used transmission inspection systems, backscatter imaging involves positioning both radiation source and detectors on the same side of a target object. Such systems are exceptionally useful in situations where access to the inspected object is limited to a single side, making X-ray transmission systems impractical.Conventional backscatter inspection systems have a significant limitation in their ability to penetrate even moderately dense objects. Moreover, the signal is dominated by the front interrogated layer, e.g., the metal wall of a container or vehicle, or the front layer of wall. To overcome this fundamental limitation, we develop an advanced inspection technique, DeepBx, which uses energy- and current- modulated X-ray pulses; fast, time-resolving X-ray detectors; and an image "peeling" processing algorithm.This publication presents the results of a simulation of the DeepBx approach and testing of a lab prototype of the DeepBx Imager, configured for the of detection of prohibited substances hidden in a wall phantom. These results are compared with conventional backscatter imaging approaches.