| 摘要 |
A method is for determining correction coefficients or parameters, in particular channel correction coefficients and/or spacing coefficients, for detector channels for a computed tomograph. In the method, a scan is carried out in order to obtain a sinogram of a phantom which is formed with a smooth cross-sectional profile and is inserted into the computed tomograph in such a way that two or more different attenuation values are detected in a full scan of virtually all the detector channels. Attenuation profiles that are obtained from the sinogram are subjected to high-pass filtering for each projection of the scan, in order to obtain discrepancies of an ideal profile which is predetermined by the phantom. A model function is matched to the discrepancies that are obtained for each of the detector channels as a function of the detected attenuation values, from which the coefficients or parameters are obtained. The method allows the channel correction coefficients to be determined easily, and the spacing coefficients also can be determined easily at the same time.
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