Real-time X-ray fan-beam z-axis position measurement

Precise control of fan-beam position is important to the production of highest quality CT images; failure to maintain fan-beam orientation can produce image artifacts. This paper describes a special technique which provides accurate real-time measurement of fan-beam z-axis position. A geometrical mask set is used to modify the response of conventional detector cells. Data from the masked detector cells are used to form a self-consistent normalized position signal which is independent of radiological dose.<
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