US 4,052,618 A · Apparatus for examining a body by radiation such as X or gamma radiation

Abstract

Computerized tomographic apparatus is disclosed wherein respective edge value signals, indicative of the absorption suffered by penetrating radiation, such as X-radiation, on traversing each of a large number of substantially linear paths through a cross-sectional slice of a body, are acquired and processed in order to produce a representation of the absorption of said radiation at many locations distributed over the slice. It is disclosed that the acquisition of said edge value signals can be carried out in a number of different ways and that the processing is effected in accordance with a compensated layer gramming technique. It is also disclosed that the radiation can be periodically interrupted and moreover that the processing is preferably carried out, without transformation of the edge values out of the space domain, on the basis of a store having an address corresponding to each of the said locations and distributing to each address values derived from paths intersecting the corresponding location as well as contributions from other paths which do not intersect the said location, said contributions being dimensioned to compensate for the fact that any path intersecting one location also intersects other locations.

Claims5

Dependent claims

Medical radiographic device for diagnostic examination of a substantially planar region of the interior of the body of a patient, comprising:

a. means disposed, outside the body, for generating a spread of penetrating radiation which propagates substantially along the plane of the region and emerges therefrom after suffering absorption determined at least in part by its path through the body, said radiation traversing the body at a selected initial mean angle determined by an initial position of the generating means with respect to the body;
b. means for causing relative motion between the generating means and the patient to cause orbiting of the generating means about the body and the generation of said spread of penetrating radiation at a corresponding succession of further mean angles;
c. detector means comprising a plurality of detectors with apertures causing each detector to receive radiation at one time along a respective beam path, the beam paths respective to the different detectors being included within said spread of radiation and diverging from each other on moving away from said generating means;
d. said detector apertures moving relative to said generating means so that each detector receives radiation along a respective beam path through the body which successively assumes different angular positions within said spread;
e. means for deriving signals from the respective detectors relating to the radiation received along the respective beam path, each detector providing a sequence of output signals as orbiting occurs relating to the radiation received at many positions relative to the body;
and
f. means for combining the signals derived from said plurality of detectors to form an image of said region, said image comprising a pattern of image elements, each image element corresponding to an element of said region.

4 more elements

Dependencies are inferred from the claim text.

Apparatus for examining a body by radiation such as X or gamma radiation

Life of this patent

Apparatus for examining a body by radiation such as X or gamma radiation

Life of this patent

Abstract

Claims5