Detection of radiation
AssigneeEMI Limited
InventorsDavid John Gibbons, Wieslaw Antoni Karwowski, Charles Phillip Cousins, Ian MacDonald Green, John James Jarrett
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Abstract
In a computerized axial tomographic apparatus it is proposed to use, as radiation detectors, alkali halide scintillator crystals cooperating with photodiodes to measure the light output therefrom, or else photodiodes directly sensitive to the radiation passed through the patient. For advantageous operation, especially in regard to drift and rapidity of operation, it is proposed to use the photodiodes photovoltaically and in the so-called "current mode".
Claims11
In a rotation only scanner for computerized axial tomography, an arrangement for detecting ionizing radiation simultaneously emergent from a body along a plurality of substantially co-planar beam paths, said arrangement comprising a detector element for each of said paths, each element including a semi-conductive device having a p-n junction region operated in the photovoltaic current mode.
Radiographic apparatus including means defining a patient position, a source of ionizing radiation, such as X-radiation, arranged to project said radiation through said position along a group of divergent and substantially co-planar beam paths, scanning means for scanning said source relative to said position along further groups of beam paths substantially co-planar with said first-mentioned group, detector means for detecting the radiation emergent from the body along each of said beam paths, said detector means comprising a plurality of detector elements and containing at least a sufficient number of said elements such that one element is provided for each path of a group;
- each element including a semi-conductive device having a p-n junction operated in the photovoltaic current mode.
Dependencies are inferred from the claim text.