An electron beam generator includes a cathode having a distal end portion emitting an electron beam, a first electrode accommodating the distal end portion, and a second electrode surrounding the first electrode when viewed from a direction along an emission axis of the electron beam. The first electrode has a first side wall surrounding the distal end portion. The second electrode has a second side wall separated from the first side wall and surrounding the first side wall. The first side wall is provided with a first opening portion allowing a first space surrounded by the first side wall and a second space between the first side wall and the second side wall to communicate with each other. The second electrode is provided with a second opening portion opening in the direction along the emission axis such that the second space and an external space communicate with each other.

An arrayed X-ray source and an X-ray imaging apparatus are described. An example X-ray source includes a housing and X-ray generators located in the housing. The X-ray generators are arranged in an array. The X-ray generators are provided separately from each other and configured to emit X-rays independently of each other.

The present invention relates to a novel, non-rotating tomographic imaging system, including a multi-source x-ray imaging module which includes multiple x-ray sources within a vacuum manifold, each equipped with a non-thermionic cathode which can reduce image scan time (and hence, motion artifacts), or delivered radiation dose, through under-sampled acquisition sequences, and without adding additional sources. The non-thermionic nature of the cathode enables rapid on/off switching of x-rays without concern as to the thermal mass or the thermal time-constant of the cathode. The modules can be flexibly interconnected to each other to allow configuration as part of a distributed ring of sources, or in other x-ray imaging geometries. Modularity provides the present invention an advantage in making it easier to debug and repair a distributed-source imaging system, such as a computed tomographic (CT) system.

Systems and methods for medical imaging. The method may include acquiring a tube voltage switching waveform for a radiation source of a medical device. The method may include determining a tube current switching period based on the tube voltage switching waveform. The method may include determining a sampling period correlated with the tube current switching period. The method may include acquiring projection data according to the sampling period. The method may further include reconstructing an image based on the acquired projection data.

A receptacle for receiving a plug connector of a high-voltage cable for a microfocus X-ray tube with a cathode, which has a metal filament and grid cap. The receptacle has a ceramic insulator with three contiguous cavities. The first cavity near the filament includes electrical contacts for the filament and the grid cap. The second cavity includes spring contacts for supplying current to the filament and a center pin for supplying voltage to the grid. The third cavity receives the plug connector. The insulator has a removable grid mounting which is conductively connected to the grid cap of the cathode. The first and second cavities are surrounded in the radial direction by the grid mounting. An air gap extends radially between grid mounting and ceramic body. At the end of the grid mounting remote from the filament is a circumferential groove in the axial direction between the grid mounting and the ceramic insulator.

The present invention relates to an apparatus for generating X-rays. It is described to produce (210) with a power supply (30) a voltage. A cathode (22) of an X-ray source (20) is positioned (220) relative to an anode (24) of the X-ray source. Electrons are emitted (230) from the cathode. Electrons emitted from the cathode interact (240) with the anode with energies corresponding to the voltage. X-rays are generated (250) from the anode, wherein the electrons interact with the anode to generate the X-rays. The X-ray source is controlled (260), such that a plurality of first X-ray pulses is generated each having a first X-ray flux, wherein the first X-ray pulses are temporally separated from each other. The X-ray source is controlled (270), such that a least one second X-ray pulse is generated having a second X-ray flux that is substantially less than the first X-ray flux, wherein the at least one second X-ray pulse is generated temporally between consecutive pulses of the first X-ray pulses.

Provided is an arc-shaped multi-focal point fixed anode gate controlled ray source, comprising an arc-shaped ray source housing, a ray tube bracket, a plurality of fixed anode reflected ray tubes and a plurality of gate controlled switches, wherein the plurality of fixed anode reflected ray tubes are fixed on the arc-shaped ray source housing by means of the ray tube bracket, and the focal points of the plurality of fixed anode reflected ray tubes are distributed on the same distribution circle; and the plurality of gate controlled switches are correspondingly connected to the plurality of fixed anode reflected ray tubes. By splicing the plurality of arc-shaped multi-focal point fixed anode gate controlled ray sources into an integral ring stricture, the focal points of all the fixed anode reflected ray tubes therein can be distributed on, the same distribution circle.

A beam injector may include a cathode emitter to emit electrons and an electrode to bias at least a portion of the electrons to remain on the cathode emitter and focus the emitted electrons into an electron beam. The beam injector may also include a resistor coupled between the cathode emitter and the electrode and configured to allow self-regulation of a voltage potential on the electrode based at least in part on a current of the electron beam.

Embodiments provide a stationary X-ray source for a multisource X-ray imaging system for tomographic imaging. The stationary X-ray source includes an array of thermionic cathodes and, in most embodiments a rotating anode. The anode rotates about a rotation axis, however the anode is stationary in the horizontal or vertical dimensions (e.g. about axes perpendicular to the rotation axis). The elimination of mechanical motion improves the image quality by elimination of mechanical vibration and source motion; simplifies system design that reduces system size and cost; increases angular coverage with no increase in scan time; and results in short scan times to, in medical some medical imaging applications, reduce patient-motion-induced blurring.

The present invention relates to an apparatus for generating X-rays. It is described to produce (210) with a power supply (40) at least two voltages between at least one cathode (20) and an anode (30), wherein the at least two voltages comprises a first voltage and a second voltage. The at least one cathode is positioned relative to the anode. Electrons are emitted (220) from the at least one cathode. Electrons emitted from the at least one cathode are interacted (230) with the anode with energies corresponding to the at least two voltages. X-rays are generated (230) from the anode, wherein the electrons interact with the anode to generate the X-rays. First X-rays are generated when the power supply produces the first voltage and second X-rays are generated when the power supply produces the second voltage. The power supply is controlled (250), such that a ratio between the first X-rays and the second X-rays is controllable.