Patent ID: 9081103
Filing Date: 2015-07-14
Classification: G01T

Abstract:
1. A method for photon counting imaging for single X-ray counting using a layer of photosensitive material, an L×K array photodetector elements arranged in the layer of the photosensitive material, an N×M array of readout unit cells including amplifying elements, K, L, M and N being numbers greater than or equal to one, at least one readout unit cell for at least one photodetector element, said at least one readout unit cells being controlled via signal processing elements, each said readout unit cell comprising internal signal processing elements allowing to generate a discriminator output signal representing an amplified signal of electron-hole pairs generated by at least one incident photon in said at least one photodetector element, the discriminator output signal being generated by comparing the amplified signal with a predetermined threshold level and the discriminator output signal being generated whenever the amplified signal exceeds the predetermined threshold level with a counter unit registering counts as a function of the discriminator output signal, said method comprising the steps of: registering the counts by counting for each signal pulse a number of dead time intervals of a predetermined width corresponding to a width of the signal pulse at the discriminator output by starting a dead time interval whenever the amplified signal initially exceeds the predetermined threshold level; and, counting directly succeeding dead time intervals for as long as the amplified signal exceeds the predetermined threshold level.