Linear array X-ray scanners

The availability of integrated circuits paved the way for the next generation ofX-ray inspection system. These units featured a side-shooting fan beam of X-rays incident on an extended array of scintillators optically coupled to photodiodes or phototransistors. The resulting low-level electric currents were then amphfied, integrated, and electronically sampled and digitized. Such systems were under development by ScanRay and Picker in 1977. By 1979, Picker was marketing 

The 1985 tragedy of Air India Flight 182, which exploded off Ireland en route from Montreal to London, stimulated an intensified effort to thwart terrorists. The International Security and Development Act of 1985 provided for air marshals and expanded FAA s R D for airport security. Thermal neutron analysis (TNA) and a number of sniffer technologies for trace explosives detection, which had been developed under FAA sponsorship, were accelerated toward commercial production. 

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