Abstract: The invention relates to a method of determining the share of different chemical elements in a layer of an examination zone. The Compton scattered radiation and the Rayleigh scattered radiation are separately determined and the variation of the differential scatter coefficients derived from the measurement values is influenced by the shares of the various chemical elements contained in the individual pixels. Therefore, the share of these chemical elements can be determined therefrom.

Abstract: The invention relates to a method of determining the Compton profile of an object to be examined which is situated in an examination zone. The examination zone is irradiated by a monochromatic primary beam whose energy is chosen so that the attenuation of the primary radiation is due essentially only to the Compton Scattering. The scattered radiation is measured in an energy resolving manner and therefrom, as well as from the attenuation in the primary beam, the Compton profiles for the individual pixels in the examination zone are determined.

Abstract: A method and apparatus for measurement of an energy-independent attenuation factor in a predetermined area of a primary X-ray beam which passes through a test object. Two detectors measure scattered radiation on closely adjacent paths in each of two different spectral ranges. The attenuation factor is calculated from the difference of the logarithms of quotients of measurements taken at different engergies.

Abstract: The invention relates to a method for determination of the cross-sections for elastic scattered radiation in which a polychromatic radiation source is used but in which good differentiation between various substances is still possible.

Abstract: The invention relates to an X-ray apparatus which allows for the determination of the elastically scattered X-rays and the evaluation of the information contained therein. Because the scattered radiation exhibits a pronounced maximum value as a function of the scatter angle and because the scatter angle at which this maximum value occurs depends on the material in which the scattered radiation is produced, X-ray images thus formed contain essential information concerning the chemical composition of the body examined.

Abstract: The invention relates to a device for examining a body by means of gamma rays or X-rays, in which a body to be examined is irradiated by a plurality of primary beams having a comparatively small cross-section. The scattered radiation produced is intercepted by detector devices, at least one of which is associated each time with a respective primary beam, and the detector device and an associated slit which images the primary beam on the detector device is arranged so that the detector device is struck essentially only by scattered radiation from this one primary beam. Preferably, the detectors are arranged between the body to be examined and the radiation source, so that they can intercept only the back-scattered radiation.

Abstract: A device for reducing artefacts in layer images. Several layer images are formed of an object layer by irradiation from different directions. The same points of these layer images are compared in order to obtain a corrected layer image: when corresponding image information is present in all image points compared, the image information is transferred to corresponding layer image points in a corrected layer image; when the image information in the compared image points is not the same, that information is at least partly suppressed.

Abstract: When only a part of a body slice to be examined, for example, a separate organ, is irradiated by means of a fan-shaped radiation beam during computer tomography, it is necessary to know the body contour in order to enable reconstruction. The body contour can be determined by means of radiation scattered in the body. The scattered radiation is measured, in a direction which deviates from the direction of the X-rays of the fan-shaped beam, along scattered radiation paths which do not intersect each other in the positioning zone. On the basis of the detected scattered radiation, the scattered radiation path which is situated most far from the center of the examination zone is selected, after which the position of the scattered radiation path within the fan-shaped radiation beam, and hence within the positioning zone, is recorded.

Abstract: Devices that measure the electron density in a body by means of radiation scattered from a narrow pencil beam of penetrating radiation directed through the body, produce defective images on reconstruction of the density distribution because of multiple scattering of radiation. This can of course be reduced by scattered ray diaphragms, but cannot be eliminated entirely. The invention therefore provides a means for detecting the size of the multiple scattered radiation component be measurement. For this purpose, the detector array which measures radiation including the single scattered radiation, is screened, at least osscasionally, from the single scattered radiation and the detected intensity values measured by the detector elements when so screened, are used to correct the values generated by measuring the detected radiation including the single scattered radiation.

Abstract: In a device for determining the density distribution on a straight line by means of a narrow penetrating beam, the measuring accuracy for the center of an object to be examined is increased in that the primary beam is not only displaced perpendicularly to its direction, but is also rotated around a point in this center. To this end, a radiation source and a detector device are mounted on a supporting device which can rotate the path of the primary beam around a central point, preferably the center of the object, around an axis which intersects the path of the primary beam at right angles.

Abstract: The invention relates to a device for measuring a scatter coefficient distribution in a plane of a body. The plane is irradiated in different directions by a primary radiation beam along beam paths which are each time situated in parallel in a direction. Scattered radiation which is generated by a primary radiation beam along its path is measured by detectors which are situated on both sides of the plane and which enclose the body as completely as possible. The scatter coefficient distribution is determined by iteration by calculating a scatter value for each beam path from an assumed distribution and by comparing this scatter value with the associated measured scattered radiation. From the difference between calculated and measured values a correction is determined and taken up in the calculated value.

Abstract: A body is irradiated by a primary radiation beam; the scattered radiation produced thereby is incident on a detector device consisting of a plurality of detectors and is a measure for the density distribution of materials in the primary beam. However, this gives rise to multiple scattered radiation which disturbs the measurement. The present invention provides a device in which disturbance by multiple scattered radiation is greatly reduced, without any significant effect on the scattered radiation originating from the primary beam. A device in accordance with the invention is provided with flat laminations which are arranged between the primary beam and the detector device and which are aligned with the primary beam in a fan of flat planes.