| 摘要 |
The invention relates to a method and a device for the X imaging of a body, that comprises n X-ray source (5), a detector (11), a converter for converting intensities into data, a bearing for receiving a body (3) and mobile about a rotation axis, and a computer programmed for building a column generatrix vector and a line generatrix vector, the terms of which are constituted by the data acquired at two rotation angles differing by 90 degrees of the mobile bearing (1) about the rotation axis. An initial matrix is built with the terms of the two generatrix vectors, and the attenuation coefficient is adjusted according to a least squares method while taking into account the line and column edge values for obtaining an adjusted image. According to the invention, the computer processes the data corresponding to first (A1) and second (B1) orthogonal arcs each representing an angular fraction of 360 degrees, and defines the column generatrix vector with the data corresponding to the first arc and the line generatrix vector with the data corresponding to the second arc. In order to obtain a synthesis image of the attenuation coefficients, the method comprises selecting N pairs of arcs in order to process the entire data acquired at 360 degrees, the first arcs (An) and the second arcs (Bn) of the N pairs including one to two overlaps. The overlap reduces the distance between the detector and the rotation axis relative to the distance obtained if the arcs were jointed. |
