Abstract: A method of comparison includes the step (14) of obtaining an interior and exterior image of an object to be compared. A standard of measurements for an acceptable object is created in step (12). An automatic comparison is made in step (14) of the image of the object to be compared with the standard and a comparison report is generated in step (16) listing deviations of the image of the object to be compared from the standard for the acceptable object. An x-ray CT scanner (76) may be utilized for obtaining the images and the standard may be derived from an actual, acceptable object or from design specifications for acceptable objects. In a preferred embodiment, CAD designs are utilized to create the standards for comparison.

Abstract: A process for analyzing the contents of containers comprising obtaining a first image of the container, tilting the container, obtaining a second image of the contents of the container in the tilted position, overlaying the first and second images, and subtracting one image from the other so that contents that remain horizontal are identified and objects that tilt are substantially erased from view in the final differenced image. In one method, the container is manually or mechanically moved relative to the image taking device, such as a digital radiography device. In another method, in order to avoid parallax problems, the container and image taking device are moved together. Computed tomography can be used in combination to obtain more characterization of the contents including shapes, densities, atomic numbers, wall thicknesses, and the like.

Abstract: The present invention relates to a computer tomography system which measures the thickness and edge position of hot-rolled steel. X-rays produced by two X-ray sources are directed, through the sample being measured, to a plurality of radiation detectors. The radiation detectors measure the attenuation of the X-rays caused by the sample. The attenuation levels sensed by each detector are correlated with each detector's physical location. This information is collected as each X-ray source illuminates the radiation detectors. The collected information is triangulated or averaged, as necessary, to determine the dimensions and position of the measured sample.

Abstract: An apparatus and method of non-contacting, non-destructive, on-line dimensional analysis and flaw detection of tubular products are disclosed. The apparatus includes penetrating radiation sources and detectors arranged about the product to be examined and a high-speed data processing system which employs novel computed tomography techniques to provide high precision dimensional estimates and flaw detection. The apparatus is capable of continuously determining the outside diameter, inside diameter, wall thickness, ovality, eccentricity, and weight-per-foot over a wide range of temperatures for essentially tubular products produced on a unit or continuous basis. The apparatus can also detect process-induced flaws in the products.

Abstract: An apparatus for determining the intensity of radiation passing through an object as a set of planar beams from a radiation source is disclosed. The radiographic apparatus includes a detector array of adjoining scintillators having wall linings suitable for absorbing radiation, thereby functioning as self-colliminating detectors. The apparatus is also capable of counting the number of individual photons of primary radiation passing through an object along each path from a radiation source operating at the very high count rates used in computer-assisted tomography applications.