The present disclosure provides a reliable X-ray generating tube that forms a focus with a stable size and shape. The X-ray generating tube includes an electron gun including an electron emitting portion, a plurality of grid electrodes, and an insulating support member that supports the plurality of grid electrodes. The electron gun includes a conductive section that hides the insulating support member to prevent the insulating support member from being directly viewed from an electron through path of electrons emitted from the electron emitting portion and passing through the grid electrodes.

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.

Controlling total emission current of an electron emitting construct in an x-ray emitting device by providing a cathode, providing multiple active areas each active area having a gated cone electron source, including multiple emitter tips arranged in an array, a gate electrode, and a gate interconnect lead connected to the gate electrode, providing an x-ray emitting construct comprising an anode, the anode being an x-ray target, situating the x-ray emitting construct facing the active areas face each other, selecting a set of active areas, and activating selected active areas by conductively connecting a voltage source to their associated the gate electrode interconnect lead.

A computer tomography x-ray tube for generating pulsed x-rays is presented. The x-ray tube comprises an anode and an electron emission unit for generating a pulsed electron beam onto the anode. Furthermore, a rotation mechanism for rotating the anode characterized in that the rotation mechanism is configured for rotating the anode with an angular velocity that varies in time is comprised. The rotation mechanism may also be configured for rotating the anode such that the variation of the angular velocity in time is a continuous oscillation around a mean angular velocity ω.sub.0 in time. In a preferred embodiment the angular velocity ω (t) varies in time according to the following formula:

ω(t)=ω.sub.0+Δω sin Ωt,

wherein ω.sub.0 is a mean angular velocity. In a particular embodiment, the grid switch for generating the pulsed electron beam is comprised and the x-ray tube may be embodied as a stereo tube, in which two focal spots of electron beams are generated in an alternating manner.

An improved X-ray source is disclosed. The improved X-ray source has an enclosure, electron guns, a first set of address lines extending through the enclosure, a second set of address lines extending through the enclosure, and nodes defined by the intersection of the first and second set of address lines. Each of the electron guns is coupled to one of the nodes such that a state of each electron gun is uniquely controlled by modulating a state of one of the first set of address lines and one of the second set of address lines.

Provided are a scanning-type X-ray source and an imaging system therefor. The scanning-type X-ray source comprises a vacuum cavity (1), wherein a cathode (2) and a plurality of anode target structures (3) are arranged in the vacuum cavity (1); a gate electrode (4) is arranged in a position, close to the cathode (2), in the vacuum cavity (1); a focusing electrode (5) is arranged in a position, close to the gate electrode (4), in the vacuum cavity (1); and a deflection coil (6) is arranged in a position, close to the gate electrode (4), at the outer periphery of the vacuum cavity (1). The scanning-type X-ray source generates electron beams by using cathode (2), controls the powering-on/off of the electron beams by the gate electrode (4), and the deflection coil (6) controls the direction of motion of the electron beams, so as to complete the switching between multiple focuses.

Provided is a miniaturized X-ray tube including an extractor and provides a miniaturized X-ray tube including a filament that emit electrons if a voltage is applied, a base having two filament through-holes for fixing the filament and for connecting power to both electrodes of the filament, a cylindrical extractor in close contact with the base and surrounding the filament without being in contact with the filament, a cutoff voltage providing unit configured to apply a cutoff voltage between one electrode of the extractor and one electrode of the filament, a body that is formed of a ceramic material, surrounds the extractor, and includes one end in close contact with the base, and a target that is connected to the other end of the body, receives the electrons emitted from the filament, and emits X-rays.

Provided is an X-ray tube. The X-ray tube includes a cathode electrode, an anode electrode vertically spaced apart from the cathode electrode, an emitter on the cathode electrode, a gate electrode disposed between the cathode electrode and the anode electrode, the gate electrode including an opening at a position corresponding to the emitter, and a spacer provided between the gate electrode and the anode electrode. The spacer includes an insulator and conductive dopants doped in the insulator.

The X-ray tube disclosed herein includes an electron emission unit including an electron emission element using a cold cathode; an anode unit disposed opposite to the electron emission unit, with which electrons emitted from the electron emission unit collide; and a focus structure disposed between the electron emission unit and a target unit disposed on a surface of the anode unit that is opposed to the electron emission unit. The electron emission unit is divided into a first region and a second region which can independently be turned ON/OFF. The X-ray tube is focus-designed such that collision regions, at the anode unit, of electron beams emitted from the respective first region and second region substantially coincide with each other.

An X-ray tube of an embodiment includes an anode; and an electron emission device. In an embodiment, the electron emission device includes at least one electron emitter including at least one emission surface and at least one barrier grid, the at least one barrier grid being spaced apart from the at least one emission surface of the electron emitter and includes a definable number of individually controllable grid segments. According to an embodiment, at least one individually definable grid voltage is applicable to each of the grid segments. In a simple manner, an electron-emission device of an embodiment permits the image quality to be adjusted with minimal anode loading.