Patent ID: 7139362
Filing Date: 2006-11-21
Classification: A61B

Abstract:
1. A computer tomograph, comprising: a radiation source for emission of X-ray radiation with a predetermined intensity and a predetermined spectrum; a detector unit, including a plurality of detectors, for verification of X-ray radiation, wherein individual detectors of the detector unit are designed to receive incident X-ray quanta in the X-ray radiation and to detect the number of X-ray quanta in the received X-ray radiation whose quantum energy exceeds a predetermined threshold value; a transmission device for transmission of the information detected by the detectors in the detector unit; and an evaluation device, designed to calculate a measurement result from a measurement object through which the X-ray radiation has passed on the basis of the information detected by the detectors in the detector unit, wherein the individual detectors in the detector unit are designed to detect both the intensity and the quantum energy of the individual X-ray quanta in the received X-ray radiation, and, for each measurement period, to emit a spectrum which, in addition to information about the number of X-ray quanta of medium quantum energy received in each measurement period, and hence the intensity, also contains information about the respective quantum energy in the X-ray quanta, and thus the spectrum of the received X-ray radiation; wherein the evaluation device is also designed to calculate the measurement result from the measurement object on the basis of the information detected by the detectors relating to the intensity and quantum energy of the individual X-ray quanta in the received X-ray radiation, taking into account the intensity and the spectrum of the X-ray radiation emitted from the radiation source; wherein the detectors in the detector unit include a plurality of parallel-connected comparators, each having a threshold value and each including an associated counter, the comparators being designed to increment the respectively associated counter by one unit when the quantum energy of an X-ray quantum in the received X-ray radiation exceeds the threshold value of the respective comparator; and wherein the detectors in the detector unit include a plurality of pulse logic devices, one pulse logic device being connected downstream from the respective comparators and upstream of the respective counters, the pulse logic devices providing time normalization of the output signals from the comparators.