Systems and methods for improving x-ray sources with pulsed x-ray sources arranged in a movable arc around a central axis. Improved systems may use the functionality of the switchable x-ray sources in various configurations to provide imaging with controlled exposure of a subject to x-rays.

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.

An anode has a base member, on which an X-ray active layer is applied. A first cooling circuit with a first cooling medium extends at least in part in the base member beneath the X-ray active layer. A second cooling circuit with a second cooling medium is arranged beneath the first cooling circuit. The anode exhibits distinctly improved thermo mechanical properties.

A mechanism for cooling the anode of an x-ray tube using a phase change material to transfer heat away from the anode. The x-ray tube is joined to a sealed heat exchange chamber which contains a liquid metal as a liquid to vapor phase change material (L-V PCM). The back side of the anode is exposed to an interior of the heat exchange chamber, and a jet sprayer inside the heat exchange chamber sprays a liquid of the metal onto the back side of the heated anode. The L-C PCM evaporates on that surface to carry away the heat, and the vapor then condenses back into the liquid on the cool surfaces of the heat exchange chamber. The surfaces of the heat exchange chamber may be cooled by convection cooling. Optionally, pipes containing a circulating cooling fluid may be provide inside the heat exchange chamber.

An X-ray generation device includes: an electron gun that emits an electron beam; a target portion in which a plurality of elongated targets that generate an X-ray because of incidence of the electron beam are disposed parallel to each other; a housing that accommodates the electron gun and the target portion; and an X-ray emission window provided in the housing to emit the X-ray generated in the target portion, to an outside of the housing. The targets are disposed on the target portion to face the electron gun at a predetermined inclination angle with respect to an emission axis of the electron beam. The X-ray emission window is disposed at a position where the X-ray generated in a direction perpendicular to the target portion is transmittable through the X-ray emission window, to face the target portion at a predetermined inclination angle.

Systems and methods for improving x-ray sources with switchable electron emitters. Improved systems may use the functionality of the switchable electron emitters in various configurations to provide power regulation, multidimensional analysis, and electron beam forming so as to increase the durability and the reliability of the system. Cooling mechanisms may be used to further protect the anode from deterioration over time.

An X-ray source, which includes a resonant cavity preferably of a cylindrical shape, is excited in a microwave mode TE.sub.11p and affected by a static and non-homogeneous magnetic field that grows longitudinally. An electron beam is injected longitudinally through one of the lateral walls of the cavity and is continuously accelerated until it reaches an energy sufficient to produce X-rays after the electrons bombard a metallic target located in the plane where they stop their longitudinal movement. The profile of the magnetic field grows in such a way that it maintains the conditions of electron cyclotron resonance along the helical paths of the electrons, The device can be used to obtain radiographic images and even produce hard X-rays.

The present application provides an external thermionic cathode distributed x-ray apparatus, including a vacuum box which is sealed at its periphery, where the interior thereof is high vacuum; a plurality of electron transmitting units arranged in a linear array and installed on the side wall of the vacuum box, where each electron transmitting unit is independent to each other; an anode installed in the center inside the vacuum box, where in the direction of length, the anode is parallel to the orientation of the electron transmitting unit, and in the direction of width, the anode has a predetermined angle with respect to the plane of the electron transmitting unit; a power supply and control system having a high voltage power supply and a focusing power supply; and a transmitting control means and a control system.

An x-ray tube includes an inner wall including a target surface and an outer wall disposed about the inner wall and defining a gap therebetween. A corrugated structure is disposed in the gap and is coupled to both the inner wall and the outer wall so as to define a plurality of channels therebetween. The corrugated structure is configured to allow a coolant to flow through the channels. An area inside of the inner wall is substantially maintained at a vacuum and a filament is disposed in the area inside of the inner wall. When a sufficient voltage is applied between the filament and the inner wall, the filament emits electrons directed to at least a portion of the target surface so that the target surface emits electrons.

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.