1. A device for two-dimensional localization of current-generating events on a resistive surface, the device comprising: a resistive surface; a plurality of electrodes fixed to the resistive surface around its periphery in order to pick up currents generated by injecting current or electric charge into points on the resistive surface; and at least three current summing lines connected to the electrodes via discrete resistive components in such a manner as to obtain analog signals on said summing lines whose amplitudes are functions of the co-ordinates of said points in a predetermined reference co-ordinate system; the device including the improvement whereby: each of said electrodes is connected by means of respective resistive components to at least three summing lines in such a manner that at least two of the said lines deliver analog signals whose amplitudes are substantially linear functions of the desired co-ordinates.