| 摘要 |
<p>1478573 Tomography MEDICAL DATA SYSTEMS CORP 10 June 1975 [11 June 1974] 24765/75 Heading H4D A device for detecting gamma radiation emanating from a source and displaying its distribution comprises a head with a lead shield collimator 102 Fig. 1 with arrays 116, 118, of apertures 104 with axes directed to a common point below it, a plurality of crystal members 112, 114, each responding electromagnetically to a different one of the arrays 116, 118, the head passing over the source of radiation so that the crystal responses are displaced from one another in time when the source is displaced from the common point These responses are detected by photomultipliers and counted and fed in separate channels to computer data banks represented on an oscillographic display separately for each channel as two dimensional, mathematical or graphical representations. An analogue to digital converter and a general purpose computer both with a plurality of channels may be employed, the data being stored after processing by the computer. There may be means for collating responses from different arrays to give a single representation illustrative of depth calculations. Figs. 2 and 3 show the separate responses of crystals 112, 114, the abscissa 150 corresponding to the distance from the X2 plane of the source 130 along the Y axis. Source 130 is within the cone of detection 120. If a single crystal were used, as in prior art, the centroid of its response is midway bebetween the centroids 154, 158 of the separate responses. By absorbing correspondences with response patterns obtained by scanning known radiation distributions an unknown radiation distribution can be determined.</p> |
