An imaging module includes a plurality of cathodes and respective gates, each cathode configured to generate a separate beam of electrons directed across a vacuum chamber and each gate matched to at least one respective cathode to enable and disable each separate beam of electrons from being directed across the vacuum chamber. A target anode is fixed within the vacuum chamber and arranged to receive the separate beam of electrons from each of the plurality of cathodes and, therefrom, generate a beam of x-rays. A deflection system is arranged between the plurality of cathodes and the target anode to generate a variable magnetic field to control a path followed by each of the separate beams of electrons to the target anode.