A detecting device comprises at least one 2-dimensional set of elementary sensors of the semiconductor type for transforming energy of radiation to be detected into electric signals. Each elementary sensor is provided on one side with an anode and on the opposite side with a cathode adapted to be electrically connected on a circuit for reading and operating on the signals. The anodes are electrically interconnected to constitute a plurality of anode subsets electrically connected at least in pairs to a measuring anode path looped on said reading and operating circuit. Each anode is connected to two separate measuring anode pats. The cathodes are electrically interconnected to constitute adjacent cathode subsets, each cathode subset being electrically connected to a measuring cathode path. The anodes belonging to two anode subsets and connected to a common anode path are associated with sensors whereof the cathodes belong to separate cathode subsets.