SCATTERED RADIATION IMAGING APPARATUS

A flying-spot pencil beam generating unit is arranged under a conveyor. A backscatter detector is located between an upper belt and a lower belt of the conveyor. Thus, this apparatus is set up to be perpendicular. A pencil beam is irradiated upward and scans an object on the belt of the conveyor by the flying-spot pencil beam generating unit, as the conveyor carries the object to be inspected. The backscatter detector gathers Compton scatter X-rays transmitted through the upper belt, as they reflect back from the object. A CPU produces a backscatter image based on the detection signal output from the backscatter detector. The backscatter image is shown on a display unit to enable detection of low-Z materials, such as plastic explosives and narcotics. In addition to the backscatter imaging, the unit may retain use of a transmitted image to thus reliably detect metal-based weapons such as guns.