Abstract: In a computed tomography X-ray system, the number of A/D converters required to digitize detector output signals is reduced without degrading the resultant tomographic image. This hardware reduction results from combining certain detector output signals into a pseudo detector having a single output. The detector output signals thus combined represent data corresponding to X-ray beams having substantially the same Radon radius. Preferably such X-ray beams also traverse substantially the same region of the CT system's reconstruction circle. Where the pseudo detector includes the output signals read from N sequentially scanned detectors D.sub.i, where i=1 denotes the first read detector and i=N the last read detector, the output of each detector D.sub.i is delayed a time (N-i).tau., and the thus delayed outputs are summed together to provide the pseudo detector output. In the above relationship, .tau. is the interval between reading adjacent detectors D.sub.i and D.sub.i+1.

Abstract: An x-ray detector includes a scintillation element having a radiation entry side and a radiation exit side disposed in succession in a direction of radiation propagation, with respective photosemiconductor layers in optical contact with the scintillation element being disposed on both the radiation entry side and the radiation exit side of the scintillation element. The layers on each side are separated to form a succession of discrete photodiodes, and the photodiodes on one side of the scintillation element may be offset relative to the photodiodes on the other side of the scintillation element.

Abstract: A computer tomography apparatus has an x-ray source with a focus, with the focus being periodically deflected during data acquisition, specifically during mean value formation of the signals obtained by the radiation detector. The mean value formation is not undertaken simultaneously for all detector elements, but instead is undertaken chronologically offset from detector element to detector element. A memory in which the analog measured values available at the end of an interval would be stored is thus not needed.