Computer tomograph system - rotates source around circular track around body and swings source so that beam is sent out at different distances to the body centre

摘要

Between the source and detector is located the body of a patient within a radius (R). A control circuit is provided for the positioning of source, body and detector. The source is positioned along a circular track of radius r around the body, in a number of positions. The control circuit uses the following to position source, body and detector field: B = j x b A = l x A + (j mod M) x C + d where B is the position of the source on a circular track. A is the angle between a central beam running from the source (Q) to the centre of the circle, and the course of each beam spread from the source mod M is the remainder from the division of j by m; j = 1,2 .. and b = 360 degs./P p is the number of measurement positions of the source around the circle, and is selected as an odd number. The spread angle A for each individual beam is determined from the sum of three angles. a = angle between 2 neighbouring detector cells M = number of different spread angle which the detector field captures relative to the source c and d are determined from the selected geometry r/R of the computer tomograph.