Aperture system for multi-source tomography and a multi-source tomography arrangement including said aperture system

摘要

In a multi-source multi- perspective tomography arrangement, a group of sources 1, 2 and 3 located in a plane E are flashed simultaneously to generate beams 10, 11, 12 limited by apertures in a diaphragm so as to overlap at an examination region 15 in a body 14 under examination. A multiperspective radiograph 17 is thereby formed from which a sectional image lying e.g. in the plane 13 can be synthesised e.g. by multiple overlapping projection. Hitherto, to vary the size of the irradiated region 15, a diaphragm with several sets of distributed apertures was required. The improvement comprises an aperture system B formed by two adjacent diaphragm plates B1 and B2 having therein respective corresponding apertures 7a, 8a, 9a and 7b, 8b, 9b which mutually overlap to form effective beam limitation apertures, and means V for displacing the plates B1, B2 relative to one another to vary the size of the beam limitation apertures. Several groups of sources in respective planes can each be limited by a corresponding pair of diaphragm plates provided non-limiting apertures are provided in each diaphragm set for beams relating to other source groups. IMAGE