| 摘要 |
The present invention relates to the correction of a detector signal d by superposing the detector signal with a correction signal. For providing a valid correction signal, a sampling pulse Ps is periodically or randomly provided. This sampling pulse serves as the initiator for sampling a process signal p of a process unit (14), which is configured to process the corrected detector signal. During the sampling of the process signal, the process signal is observed. In case a pulse at the process signal is detected, the sampling is assumed as not being suitable to correct the detector signal, since the pulse affects the process signal. Otherwise, namely in case such a process signal pulse does not occur during the sampling period, the process signal is further observed during a validation period, which is subsequently arranged to the sampling period. This validation period is used to validate, whether the sampled process value of the process signal has already been influenced by an upcoming pulse at the process signal. In case the sampling is assumed as valid, the sampled process value is used as a basis for providing, in particular setting or updating, the correction signal. An updated or a new set correction signal in turn changes the baseline of the corrected detector signal. As an effect of the invention, the baseline of the corrected detector signal may be corrected independent of the direct knowledge of a timing, at which an X-ray source provides X-ray radiation to the object-receiving space and/or at least a part thereof to an X-ray detector (42). Therefore, the invention may be applied to any X-ray imaging system, independently of the knowledge, when X-ray quanta and/or X-ray photons impinge on the X- ray detector. |
