Ionizing radiation detection based on dual-energy scanning.

A radiation detecting apparatus based on dual-energy scanning, comprising: a plurality of detectors (16) stacked line; and a device (17-19, 21-22) for scanning said plurality of detectors (16) stacked line object to be examined while each of said plurality of detectors (16) stacked line is exposed an ionizing radiation beam, which has collided on said object, to thereby record a plurality of line images of said object; and a filter device arranged in the path of said beams of ionizing radiation upstream of said object to filter said ionizing radiation beams, characterized in that the filter device comprises an array of sections (62, 63) of filter aligned with said beams ionizing radiation during scanning so that each of said ionizing radiation beams will have been filtered by a respective one of said sections (62, 63) when impinging on said object, where every second filter section in the array has a first filter characteristic and the other filter sections formation have each a second filter characteristic; and said device (17-19, 21-22) for scanning said plurality of detectors (16) stacked line is arranged to scan at least a distance corresponding to twice the distance between two detectors (16) of adjacent stacked line said plurality of detectors (16) stacked line.