| 摘要 |
In transversal tomography devices in which the X-ray beam and the array of detectors are such that they cover the higher slice to be examined, a very large array dynamic range (the ratio between the largest detector signal and the smallest detector signal occurring during a measurement) occurs. The array dynamic range often lies between the values 104 and 2.104. By adaptation of integration capacitances of the integrators connected to the detectors to the position of the detector in the array, the array dynamic range can be reduced. If the ratio between the largest integration capacitance (at the end of the row) and the smallest integration capacitance (in the center of the array) equals, for example, 40, the array dynamic range is substantially smaller than 1000. The advantage consists in that less severe requirements are imposed on the signal processing section connected to the integrators.
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