A method in an X-ray source configured to emit, from an interaction region, X-ray radiation generated by an interaction between an electron beam and a target, the method including the steps of: providing the target; providing the electron beam; deflecting the electron beam along a first direction relative the target; detecting electrons indicative of the interaction between the electron beam and the target; determining a first extension of the electron beam on the target, along the first direction, based on the detected electrons and the deflection of the electron beam; detecting X-ray radiation generated by the interaction between the electron beam and the target; and determining a second extension of the electron beam on the target, along a second direction, based on the detected X-ray radiation.

A magnetic assembly for focusing an electron beam includes one or more quadrupole assemblies, each quadrupole assembly having at least a pair of separate opposing members with angular pole extensions of one opposing member facing angular pole extensions of another opposing member. An X-ray tube includes a magnetic assembly for focusing an electron beam extending from a cathode to an anode of the X-ray tube, the magnetic assembly comprising one or more quadrupole assemblies, each quadrupole assembly having at least a pair of opposing members with angular pole extensions of one opposing member facing angular pole extensions of another opposing member.

In the present invention, a computed tomography system, an X-ray tube used therein and a cathode assembly disposed in the X-ray tube, as well as an associated method of use, is provided that includes a gantry and the X-ray tube coupled to the gantry. The X-ray tube includes the cathode assembly having a pair of emitters for generating an electron beam, where the pair of emitters are disposed in the casing at angles with respect to one another. The X-ray tube further includes a focusing electrode for focusing the electron beam, an extraction electrode which electrostatically controls the intensity of the electron beam, a target for generating X-rays when impinged upon by the electron beam and a magnetic focusing assembly located between the cathode assembly and the target for focusing the electron beam towards the target.

A cathode head can include: a first electron emitter filament having a first size; a first grid pair defining walls of a first filament slot having the first filament therein, each grid member of the first grid pair being electronically coupled to different voltage sources; a second electron emitter filament; and a second grid pair defining walls of a second filament slot having the first electron emitter therein, each grid member of the second grid pair being electronically coupled to different voltage sources. The first grid pair can have a first and second grid members; and the second grid pair can have the second grid member and a third grid member. The first grid member and third grid member are electronically coupled to the same voltage source and the second grid member being electronically coupled to a different voltage source.

A method is for controlling an X-ray tube including at least one grid electrode arranged between an anode electrode and a cathode electrode. In an embodiment, the method includes focusing, via a focusing unit, a flow of electrons from the cathode electrode to the anode electrode; applying in a first switching state, a first electrical grid potential to the at least one grid electrode via a switching unit, to pinch off the flow of electrons between the anode electrode and the cathode electrode; and applying in a second switching state, a second electrical grid potential to the at least one grid electrode to enable the flow of electrons, at least the second electrical grid potential being provided by the focusing unit.

A method may include obtaining a feedback or a reference value of a tube voltage applied to a radiation source of a radiation device for generating radiation rays. The method may also include determining, based on the feedback or the reference value of the tube voltage, a specific value of a focusing parameter associated with a focusing device of the radiation device. The method may further include causing the focusing device to shape a focus of the radiation rays according to the determined value of the focusing parameter. The focus of the radiation rays may satisfy an operational constraint under the specific value of the focusing parameter.

An X-ray generation device includes a cathode including an electron source generating an electron beam, an anode including a target to transmit an X-ray generated by collision of the electron beam, and a convergence electrode converging the electron beam toward the target. The target has a first region having a locally small thickness and a second region having a larger thickness than the first region. The X-ray generation device further includes a deflection unit to switch an incident position of the electron beam between the first region and the second region. The deflection unit has an adjustment mode to adjust an X-ray focal spot diameter and an X-ray generation mode to generate an X-ray, the electron beam is caused to enter the first region in the adjustment mode, and the electron beam is caused to enter the second region in the X-ray generation mode.

According to one embodiment, an X-ray tube includes an elongated anode target, a cathode, and a vacuum envelope. The cathode includes an electron emission source and a converging electrode including a trench portion. The trench portion includes a closest inner circumferential wall, an upper inner circumferential wall, and a lower inner circumferential wall. The electron emission source projects towards a opening of the trench portion from a boundary between the closest inner circumferential wall and the upper inner circumferential wall.

An example embodiment includes a cathode assembly. The cathode assembly includes a cathode head, a filament, a focusing structure, and a non-rectilinear focusing aperture. The cathode head defines a filament slot. The filament is positioned in the filament slot that is capable of emitting electrons by thermionic emission. The focusing structure is positioned at least partially between the filament and an anode. The non-rectilinear focusing aperture is defined in the focusing structure. The non-rectilinear focusing aperture is configured to shape an emission profile of electrons emitted by the filament.

An X-ray generation tube includes: an anode including a target configured to generate X-rays under irradiation of electrons, and an anode member electrically connected to the target; a cathode including an electron emitting source configured to emit an electron beam in a direction towards the target, and a cathode member electrically connected to the electron emitting source; and an insulating tube extending between the anode member and the cathode member. The anode further includes an inner circumferential anode layer electrically connected to the anode member, the inner circumferential anode layer extending along an inner circumferential face of the insulating tube, and is remote from the cathode member.