A device and method for creating beam formed X-Ray radiation using radio frequency (RF) modulated field emission X-ray sources is described. A radio frequency RF source generates a RF control signal which is supplied to an array of phase delay elements to generate multiple individually controlled phase delayed RF signals. These are then directly provided to each of a plurality of field emission sources (via a matching circuit) to generate a plurality of RF modulated electron current, or beam, each at the same frequency and phase delay of the phase delayed RF signals. Each of the electron beams impacts a target anode to generate X-rays also at the same frequency and phase delay of the phase delayed RF signals. By controlling each of the phase delay elements a beamformed X-ray radiation pattern can be generated.

A vacuum electron tube comprises at least one electron-emitting cathode and at least one anode arranged in a vacuum chamber, the cathode having a planar structure comprising a substrate comprising a conductive material, a plurality of nanotube or nanowire elements electrically insulated from the substrate, the longitudinal axis of the nanotube or nanowire elements substantially parallel to the plane of the substrate, and at least one first connector electrically linked to at least one nanotube or nanowire element so as to be able to apply a first electrical potential to the nanowire or nanotube element.

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 a rotary anode X-ray source. In addition to a primary cathode of a rotary anode X-ray tube, an auxiliary cathode is provided in the rotary anode X-ray tube. Electrons from the auxiliary cathode are focused into an area on the anode, from which X-rays cannot enter the used X-ray beam generated by the primary cathode. An emission current controlling device is used to control the electron emission of the auxiliary cathode. Thus, the voltage down-ramp for dual energy scanning is kept constant even though the primary X-ray output changes for the sake of dose modulation or during a transient of the primary electron current.

The present disclosure provides a cathode emission device. The cathode emission device may comprise a cathode assembly, including: a first filament, a second filament, and a grid electrode. The grid electrode may be operably connected to the first filament and surrounding the first filament and the second filament. The cathode assembly may be configured to be operably connected to a high-voltage generator and switchable between a first connection configuration and a second connection configuration.

An x-ray tube having at least one focusing cup and an anode. The x-ray tube may have a first filament positioned in a first location between the focusing cup and the anode, the first filament having a first size, and a second filament positioned in a second location between the focusing cup and anode, the second filament having a second size that is substantially the same as the first size. The x-ray tube may also include a switching mechanism configured to engage the second filament upon failure of the first filament.

At least one example embodiment provides an electron emitter apparatus having a first ring of field-effect emitter needles, the field-effect emitter needles of the first ring forming a first emitter surface on an inner side of the first ring; and a second ring of field-effect emitter needles, the field-effect emitter needles of the second ring forming a second emitter surface on an inner side of the second ring, wherein the first ring and the second ring are arranged in such that the first emitter surface and the second emitter surface form a substantially contiguous three-dimensional overall emitter surface, the substantially contiguous three-dimensional overall emitter surface defining a hollow channel along a longitudinal axis of the electron emitter apparatus.

In some embodiments, a cathode assembly may include a cathode head that has a first electron emitter and a second electron emitter. The first electron emitter may have a first connection location and a second connection location. The second electron emitter may have a third connection location and a fourth connection location. The third connection location may be electrically coupled with the second connection location of the first electron emitter. The cathode assembly may include a receptacle having a first connector and a second connector. The first connector may be electrically coupled with the first connection location of the first electron emitter. The second connector may be electrically coupled with the second connection location of the first electron emitter and the third connection location of the second electron emitter. The third connector may be electrically coupled with the fourth connection location of the second electron emitter.

Some example embodiments provide an x-ray tube for a stereoscopic imaging having an evacuated x-ray tube housing; an electron emitter apparatus in the x-ray tube housing, the electron emitter apparatus including a first field effect emitter with a first emitter surface and a second field effect emitter with a second emitter surface, at least one of the first emitter surface or the second emitter surface being segmented such that a portion of the at least one of the first emitter surface or the second emitter surface can be set relative to the respective overall emitter surface by selectively switching emitter segments of the at least one of the first emitter surface or the second emitter surface; an anode unit in the x-ray tube housing, the anode unit configured to generate x-ray radiation for the stereoscopic imaging as a function of electrons striking two focal points; and a control unit.

A computer tomograph operates by rigidly arranged x-ray tubes, which are components of emitter-detector elements, which form an emitter-detector ring opened by relocating one emitter-detector element. Each x-ray tube includes a cathode emitting electrons, and an anode arrangement having an anode. Each cathode has an orientation angle relative to the geometrical center axis of the computer tomograph. A tangential plane on the focal spot of the anode has a surface normal, which includes an anode angle with the center axis. X-ray radiation emitted from the focal spot is directed in a center radiation angle to an x-ray detector axially offset relative to the x-ray tubes. The quotient from the sum of the orientation angle, radiation angle and anode angle is between two ninths and two. Each cathode, interacting with an electrode arrangement of the x-ray tubes, produces a focal spot on one of selectable positions on the anode arrangement.