The embodiments described herein relate generally to detecting contraband, and more particularly, to detecting contraband using a system that combines X-ray detection and quadrupole resonance (QR) detection.
At least some known passenger screening systems detect contraband. As used herein, the term “contraband” refers to illegal substances, explosives, narcotics, weapons, a threat object, and/or any other material that a person is not allowed to possess in a restricted area, such as an airport. The contraband detection involves a combination of sensors and structures to control a flow of passengers. Although passengers are referred to herein, any person and/or object (i.e., subject) may be scanned using the systems and methods described herein.
For example, one known checkpoint system first screens passengers with a whole-body walk-through metal detector (WTMD). In such a checkpoint system, when a threat item or anomaly is detected from a whole body scan, the passenger is directed to a wanding station, which is a physical structure that controls the progress of the passenger. Importantly, if a threat item or anomaly is detected by the whole body scan, then the passenger may be considered a threat. As such, his or her mobility is controlled by the structure of the wanding station. Within that controlled structure, or at its egress, a security officer can use a detection wand to perform a localized scan of the passenger's body to resolve the alarm. If the passenger is then cleared, he or she may proceed beyond the physical structures of the wanding area. However, there are limits to such systems.