System for correcting the spatial gain non-uniformity in a radiation imaging device, and imaging device using the same

摘要

So as to reduce the width of the energy window used in these devices, and simplify the operations for determining each point, the invention provides, in the case of a determination by four signals A, B, C, D, for considering the largest of these four signals to the exclusion of the others, for the comparison with the reference level in this window. This operation is performed by means of four parallel- mounted diodes (4) at the positive input of an operational amplifier (1), only the diode receiving the largest of the signals being in the conducting state; adjoining arrangements (5 and 12) limit the effect of the drop in the conducting diode. Application to medical radiation imaging devices. IMAGE