A radiation detector arrangement for imaging of an object comprises multipleline detector units (41), each being arranged for one-dimensional imaging ofthe respective ray bundle. The detector units are arranged parallel in a two-dimensional array. The detector units are sited in rows (44； 61) and stacks(45； 63), the rows being parallel with the detector unit and the stacks beingorthogonal thereto, where the one-dimensional detector units in each row aretogether capable of detecting the object in one dimension. A device (87-89,91) is provided for moving the detector units relative the object parallelwith the stacks at least a distance corresponding to the distance (s1~)between two adjacent detector units in the stacks.
