Abstract: Embodiments of the disclosure relate to electron emitters for use in conjunction with X-ray devices. In one embodiment, the emitter features a round emission area capable of emitting electrons when heated, wherein the round emission area comprises at least one of a gap, a channel, or a combination thereof that separates a first portion of the round emission area from a second portion of the round emission area and permits thermal expansion of the first portion and the second portion within the at least one gap or channel without permitting the first portion and the second portion to touch one another. The two electrically conductive legs coupled to the surface at respective locations outside the round emission area and that are capable of supplying current to the round emission area.

Abstract: The different advantageous embodiments provide a method and apparatus. The apparatus comprises a moveable platform, a housing connected to the moveable platform, a power supply located inside of the housing, and an x-ray tube located inside of the housing. The power supply and the x-ray tube are immersed in a coolant. The x-ray tube is configured to generate an x-ray beam.

Abstract: A radiation generating tube includes a vacuum envelope formed by an insulating tube, a cathode and an anode. At least one of the cathode and the anode is bonded to the insulating tube via a conductive bonding material disposed between bonded surfaces facing each other. The conductive bonding material is partially protruding from between the bonded surfaces to an outer peripheral surface or an inner peripheral surface of the insulating tube. A concave portion is formed on the outer peripheral surface or the inner peripheral surface of the insulating tube adjacent to a bonded surface on an insulating tube side, and a distal end of a conductive bonding material protruding from between bonded surfaces is accommodated in the concave portion.

Abstract: A miniaturized high-speed modulated X-ray source (MXS) device and a method for rapidly and arbitrarily varying with time the output X-ray photon intensities and energies. The MXS device includes an ultraviolet emitter that emits ultraviolet light, a photocathode operably coupled to the ultraviolet light-emitting diode that emits electrons, an electron multiplier operably coupled to the photocathode that multiplies incident electrons, and an anode operably coupled to the electron multiplier that is configured to produce X-rays. The method for modulating MXS includes modulating an intensity of an ultraviolet emitter to emit ultraviolet light, generating electrons in response to the ultraviolet light, multiplying the electrons to become more electrons, and producing X-rays by an anode that includes a target material configured to produce X-rays in response to impact of the more electrons.

Abstract: An electron beam emitter for generating an electron beam to be directed towards an anode of an X-ray tube for generating an X-ray beam, wherein the electron beam emitter comprises an electrically conductive tape, made of material capable of emission of electrons, configured to be supplied with electric energy for emitting the electron beam, and a support arrangement configured for mounting the tape under permanent tension.

Abstract: An x-ray imaging system includes a detector positioned to receive x-rays, an x-ray tube configured to generate x-rays toward the detector from a focal spot surface, the x-ray tube includes a target having the focal spot surface, a cathode support arm, and a cathode attached to the cathode support arm. The cathode includes a split cathode cup having a first portion and a second portion that is separate from the first portion, the first and second portions having respective first and second emitter attachment surfaces, and a flat emitter that is attached to the first and second emitter attachment surfaces such that, when an electrical current is provided to the first portion of the cathode cup, the current passes through the flat emitter and returns through the second portion of the cathode cup such that electrons emit from the flat emitter and toward the focal spot surface.

Abstract: An apparatus for modifying an aspect ratio of an electron beam to form a focal spot having a desired size and aspect ratio on a target anode is disclosed. The apparatus includes an emitter element configured to generate an electron beam having a first aspect ratio shape and an extraction electrode positioned adjacent to the emitter element to extract the electron beam out therefrom, the extraction electrode including an opening therethrough. The apparatus also includes at least one shaping electrode positioned to receive the electron beam after passing through the extraction electrode, the shaping electrode defining a non-circular aperture therein and being configured to provide at least one of shaping and focusing of the electron beam to have a second aspect ratio shape different from the first aspect ratio shape so as to form a focal spot having a desired size and aspect ratio on a target anode.

Abstract: An electrically heated planar cathode for use in miniature x-ray tubes may be spiral design laser cut from a thin tantalum alloy ribbon foil (with grain stabilizing features). Bare ribbon is mounted to an aluminum nitride substrate in a manner that is puts the ribbon in minimal tension before it is machined into the spiral pattern. The spiral pattern can be optimized for electrical, thermal, and emission characteristics.

Abstract: A dual energy X-ray source for use in Homeland Security, Medical, Non-destructive Testing, and other markets includes a power supply, and a single x-ray tube. The X-ray tube includes two cathodes, and a single anode. The electrons from the cathodes travel predominantly along the axis of the x-ray tube, and impact the anode. The grid and/or focus coil direct the electrons so that electrons can pass by the cathode. The cathodes are kept at different potential, such that the tube can rapidly switch energies, and can rapidly switch output flux from each cathode.

Abstract: An x-ray generation device and a cathode thereof are provided. The x-ray generation device comprises the cathode, a focusing device, an anode target, and a glass container. The cathode comprises a container and an electron beam generator. The container has a base and a side wall surrounding the base, and both of them define a trench. The electron beam generator comprises at least one metal unit, each of the at least one metal unit is chemical-vapor-deposited a carbon layer, and each of the at least one metal unit is disposed on a bottom of the trench. The at least one metal unit is electrically connected to an outer metal unit of the x-ray generation device. The glass container contains the cathode, the focusing device, and the anode target in sequence. Each of the at least one carbon layer faces the anode target. The glass container has a valve for evacuating and a window for emitting an x-ray.

Abstract: An embodiment of the invention relates to a cathode cup (20) comprising a receptacle for holding an electron emitter (21), wherein the cathode cup is provided at least in the area facing the electron emitter (21) with a surface comprising a plurality of cavities (23). Further, the invention provides an electron source and an x-ray system comprising such a cathode cup (20).

Abstract: The present embodiments relate to efficient electron beam steering within X-ray tubes, for example X-ray tubes used in CT imaging. In one embodiment, and X-ray tube with enhanced electron beam steering is provided. The X-ray tube includes an electron beam source, a target configured to generate X-rays when impacted by an electron beam from the electron beam source, and a steering magnet assembly having a plurality of ferrite cores and a plurality of litz wire coils wound on the ferrite cores.

Abstract: In one embodiment, an X-ray tube includes an electron beam source including a primary cathode configured to emit an electron beam and an anode assembly including an anode configured to receive the electron beam and to emit X-rays when impacted by the electron beam. The X-ray tube also includes an enclosure, at least the primary cathode and the anode being disposed in the enclosure, and a secondary cathode disposed in the enclosure and configured to emit electrons to impact the anode for degassing the enclosure.

Abstract: A radiation source includes a vacuum chamber, means for injecting an optical wave, a cold source for emitting electrons, a power supply, an anode for emitting X-rays, and at least one window through which the X-rays exit. A light source delivers the optical wave, and the cold source includes at least one substrate with a conducting surface and is subjected to an electric field. The cold further includes a photoconductive element in which the current is controlled approximately linearly by the illumination and at least one electron-emitting element, the photoconductive element electrically connected in series between an emitting element and a conducting surface. Current photogenerated in the photoconductive device is equal to that emitted by the emitter or the group of emitters with which it is associated, and the emitted stream of X-rays is approximately linearly dependent on the illumination.

Abstract: A method for controlling emission of a beam of electrons in an X-ray imaging tube. The X-ray imaging tube has an anode and a cathode. The method comprises a step in which at least one emission device included in the cathode emits an accelerated incident beam of electrons onto an impact focal spot on the anode to generate X-rays. An emission device is associated firstly with an assembly of polarizing plates and secondly with a focusing cup. An electric generator simultaneously applies a beam focusing voltage to the assembly and/or to the cup to control a characteristic dimension of the focal spot, and a cut-off voltage to the cup to control the emission of the beam by the device. The invention also concerns a corresponding cathode, tube and imaging system.

Abstract: One example embodiment includes methods for making electron emitters. The electron emitter comprises a conductive member that defines a plurality of filament segments that are integral with each other. Each filament segment includes an intermediate portion and an interconnecting portion attached to an adjacent filament segment. The intermediate portions are substantially coplanar with each other and each intermediate portion includes a substantially planar electron emission surface.

Abstract: An x-ray tube cathode with magnetic electron beam steering. In one example embodiment, an x-ray tube cathode includes a cathode head and an electron emitter. The cathode head includes electrically conductive and non-magnetic material integrated with magnetic material. The cathode head defines an emitter slot in a portion of electrically conductive and non-magnetic material positioned between two portions of magnetic material. The electron emitter is positioned within the emitter slot. The electron emitter is configured to emit a beam of electrons. The beam of electrons is configured to be both focused by the electrically conductive and non-magnetic material and steered during beam formation by the magnetic material.

Abstract: An indirectly heated cathode assembly is presented. The indirectly heated cathode assembly includes at least one electron source for generating a first electron beam, an emitter for producing a second electron beam when heated by the first electron beam and a focusing electrode for controlling, and directing the first electron beam towards the emitter.

Abstract: A cathode assembly for an x-ray tube. In one example embodiment, a cathode assembly includes a cathode head, a filament, and first and second focusing tabs. The cathode head defines a recess having first and second open ends, a slot within the recess, and first and second tab stops within the recess. The filament is positioned within the slot. The first focusing tab is positioned in the first open end of the recess abutting the first tab stop. The second focusing tab is positioned in the second open end of the recess abutting the second tab stop.

Abstract: Multibeam field emission x-ray systems and related methods can include cathode elements, an anode assembly spaced from the plurality of cathode elements, and an extraction gate positioned between the plurality of cathode elements and the anode assembly. A potential difference can be applied between the extraction gate and at least one of the cathode elements to cause an emission of electrons from the respective cathode elements. Emission characteristics of the cathode elements can be measured, and the potential difference between the extraction gate and at least one of the cathode elements can be adjusted based on the emission characteristics measured.

Abstract: An injector for an X-ray tube is presented. The injector includes an emitter to emit an electron beam, at least one focusing electrode disposed around the emitter, wherein the at least one focusing electrode focuses the electron beam and at least one extraction electrode maintained at a positive bias voltage with respect to the emitter, wherein the at least one extraction electrode controls an intensity of the electron beam.

Abstract: An X-ray tube includes a target and a cathode assembly. The cathode assembly includes a first filament configured to emit a first beam of electrons toward the target, a first gridding electrode coupled to the first filament, a second filament configured to emit a second beam of electrons toward the target, and a second gridding electrode coupled to the second filament.

Abstract: The disclosed embodiments include embodiments such as an X-ray tube cathode filament system. The X-ray tube cathode filament system includes a substrate and a coating disposed on the substrate. In this cathode filament system, an electron beam is emitted from the coating but not from the substrate. The electron beam is produced through the use of the thermionic effect.

Abstract: Systems and methods are described for a compact x-ray system that uses optical energy for triggering x-ray generation rather than a traditional filament. A photocathode is illuminated and the ensuing electrons are directed to an anode resulting in x-ray generation, resulting in increased x-ray source durability. Pulsing, beam forming, scanning, varying x-ray characteristics, longevity of source and other desirable attributes not currently available in the state of the art are achievable, through the use of shaped, multi-materialed photocathodes, shaped, multi-materialed anodes, arrays of optical lines, and so forth, as some examples. Inexpensive, highly controllable sources such as solid-state lasers can be used, permitting a wide variety of applications and power levels.

Abstract: A cathode element for a microfocus x-ray tube includes a heatable filament formed of a wire for thermionic emission of electrons for generating an electron beam. The filament, in a source area of the electron beam, has an elongate extension in two directions perpendicular to the electron beam.

Abstract: An x-ray tube has an anode and a thermionic emitter with multiple emitter regions spaced from one another that generate, between the emitter and the anode, an electron beam composed of multiple partial beams generated by the respective emitter regions. Between the emitter and the anode is at least one control electrode arrangement that generates a variable electrical field and that has a number of passages to control the respective partial beams. Thus control electrode arrangement has a number of control electrode layers. The individual emitter regions and the control electrodes are arranged and controlled relative to one another to cause substantially the entirety of each partial beam generated by the respective emitter regions to proceed through a passage respectively associated with that partial beam.

Abstract: A device to control an electron beam for the generation of x-ray radiation, has an electron emitter to generate an electron beam, to which emitter an emitter voltage can be applied, a diaphragm, at least two control elements associated with the diaphragm to affect the electron beam, and switching arrangement with which at least two different electrical voltages can be applied to the at least two control elements. The same electrical voltage is applied to each of the at least two control elements. Upon switching the voltage, an electrical circuit that delays the setting of the respective voltage at the one control element is associated with the connection line of the one control element with the switching arrangement to switch over the voltage. The invention moreover concerns an operating method for the device and an x-ray tube provided with the device.

Abstract: A source (19) for multiple energy X-ray generation in particular by field emitting carbon nanotubes (1, 2) is presented. In order to achieve a spatial overlap of the trajectories of the X-ray beams coming from different emitters, a focusing unit (7, 9) is supplied to the emitted electrons (28, 29). A fast switching between the emission of the different carbon nanotubes allows multiple kilovolt imaging. Independent determination of multiple focal spot parameters by the focusing unit leads to the possibilities of fast switching between different spot geometries and spatial resolutions. This might be seen in FIG. 1.

Abstract: Electron emitters for x-ray tubes. In one example embodiment, an electron emitter for an x-ray tube includes an electron filament and a plurality of electrical leads. The electron filament defines a plurality of openings. Each lead is positioned so as to extend through one of the openings and each lead is mechanically and electrically connected to the filament proximate the opening without the presence of braze material.

Abstract: A multi-directional dispenser cathode has a cathode body that supports a plurality of electron emitters which spanning open portions of the cathode body. Each electron emitter has an inward facing surface and an outward facing surface wherein the inward facing surfaces and an interior wall of the body define an interior volume that contains a heater. To selectively accelerate emitted electrons, an electrically distinct biasing electrode is in spaced relationship to the outward facing surface of each electron emitter and coupled to a biasing power supply effective to provide an intermittent positive voltage potential to the biasing electrode. The distinct biasing electrodes are provided with a positive voltage potential at different times thereby causing an intermittent burst of electrons. Among the applications for intermittent bursts of accelerated electrons are to generate radiation from a particle accelerator.

Abstract: An x-ray tube having a reduced spacing between the focal spot of an anode and an adjacent end wall of an evacuated enclosure is disclosed. This in turn positions the tube relatively closer to the chest wall of a patient during mammography procedures. In one embodiment, the x-ray tube comprises an evacuated enclosure having first and second ends interconnected by a cylindrical side wall. The evacuated enclosure includes a rotor assembly having a bearing assembly and a stem. An anode is rotatably supported by the stem of the rotor assembly and includes a target surface and an opposite second surface. The target surface is positioned to face the bearing assembly, while the second surface is positioned to face the first end of the evacuated enclosure, with no intervening structure interposed therebetween. A cathode is included to emit electrons for impingement on a focal spot of the focal track.

Abstract: An x-ray generating device includes at least a nano-structure based field emission electron source having a self-aligned gate aperture incorporated on a substrate. The device further includes at least an anode target. Associated fabrication method is also described.

Abstract: A thermionic electron emitter (1) is proposed comprising an inner part (2) including a heatable flat emission surface (3) and an outer part (4) including a surrounding surface (6) substantially enclosing the emission surface and a heating arrangement for heating the emission surface to a temperature for thermionic electron emission. The outer part is mechanically connected to the inner part in a connection region (10) apart from the emission surface. Furthermore, the surrounding surface is thermally isolated, e.g. by a gap (14), from the emission surface in an isolation region apart from the connection region. By providing a surrounding surface enclosing the emission surface which may be on a similar electrical potential as the emission surface but which can have a substantially lower temperature than the emission surface without influencing the temperature distribution within the emission surface, an improved electron emission distribution and homogeneity can be obtained.

Abstract: A cathode has a cathode head in which is arranged at least one emitter that emits electrons upon application of a heating voltage. At least one series resistor is connected in the voltage feed to at least one emitter. The use of such a cathode in an x-ray tube enables x-ray exposures with a high quality.

Abstract: Scattered electron collector comprising a heat absorbing member having a first end, a second end, an outer periphery and a central bore (14, 16), wherein the central bore is formed in longitudinal direction through the heat absorbing member from the first end to the second end, and a cooling element (50) having an outer periphery and an inner periphery (52). The outer periphery (12) of the heat absorbing member is adapted to be in contact with the inner periphery of the cooling element. Further, at least one slot (20) is formed from the central bore in the direction to the outer periphery of the heat absorbing member to reduce compression stress within the heat absorbing member.

Abstract: An X-ray source with a cathode (2) that includes a first wire (4) having optionally thermal loops (12, 14) between an emission loop (10) and first and second ends (6, 8). A spiral second wire (30) is wound around the wire (4) and a low work function coating (32) is provided on both wires. The first and second wires may be of refractory material, such as tungsten, and the low work function coating may include barium oxide.

Abstract: According to the X-ray generating apparatus of this invention, a potential corresponding to that of a housing is applied to a first electrode, closest to a cathode, of at least two intermediate electrodes arranged between the cathode and a target. Therefore, even if the first electrode with an increased thermal capacity contacts the housing, the function of the X-ray generating apparatus will never be impaired. As a result, the first electrode is not easily restricted by structure, so that the first electrode may be enlarged as a measure for heat radiation, or that the first electrode may be placed in contact with the housing. The first electrode contacting the housing determines a positional relationship of the electron gun and housing to facilitate assembly of the X-ray generating apparatus. Further, all the potentials of the cathode, intermediate electrodes (e.g.

Abstract: Provided is an X-ray generator for generating X-rays from an X-ray focal point that is a region in which electrons emitted from a filament impinge upon a rotating anode. The X-ray generator has a Wehnelt electrode for surrounding the filament, an attachment part formed integrally with the Wehnelt electrode, a pedestal to which the attachment part is attached, and a casing for housing the pedestal and the anticathode. The width of the space in which the anticathode is housed by the casing is less than the width of the space in which the pedestal is housed by the casing. The Wehnelt electrode extends into the space in which the anticathode is housed by the casing, in a state in which the attachment part is attached to the pedestal.

Abstract: Provided is a field emission X-ray tube. The field emission X-ray tube includes a cathode electrode provided to one end of a vacuum vessel and including a field emission emitter, an anode electrode provided to the other end of the vacuum vessel in an extending direction of the vacuum vessel, and a gate electrode provided on an outer surface of the vacuum vessel adjacent to the cathode electrode.

Abstract: An apparatus and method comprising a cathode structure which can be a cylindrical filament coiled in a helix or which can be constructed of a ribbon or other suitable shape. The cathode structure can be heated by passage of an electrical current, or by other means such as bombardment with energetic electrons. Selected portions of the surface of the cathode structure have an altered property with respect to the non-selected portions of the surface. In one embodiment, the altered property is a curvature. In another embodiment, the altered property is a work function. By altering the property of the selected portions of the surface, the electron beam intensity is increased, and the width is decreased.

Abstract: A thermionic electron emitter (1) is proposed comprising an emitter part (2) with a substantially flat electron emission surface (3) and a bordering surface (5) adjacent thereto. In order to better absorb main stress loads (L) induced by external forces, the emitter part is provided with an anisotropic polycrystalline material having a crystal grain structure of elongated interlocked grains the longitudinal direction (G) of which is oriented substantially perpendicular to the direction (L) of the main stress loads occurring under normal operating conditions.

Abstract: An apparatus and method comprising a cathode structure which can be a cylindrical filament coiled in a helix or which can be constructed of a ribbon or other suitable shape. The cathode structure can be heated by passage of an electrical current, or by other means such as bombardment with energetic electrons. Selected portions of the surface of the cathode structure have an altered property with respect to the non-selected portions of the surface. In one embodiment, the altered property is a curvature. In another embodiment, the altered property is a work function. By altering the property of the selected portions of the surface, the electron beam intensity is increased, and the width is decreased.

Abstract: One example embodiment includes an electron emitter. The electron emitter comprises a conductive member that defines a plurality of filament segments that are integral with each other. Each filament segment includes an intermediate portion and an interconnecting portion attached to an adjacent filament segment. The intermediate portions are substantially coplanar with each other and each intermediate portion includes a substantially planar electron emission surface.

Abstract: A radiation source which can emit X-ray flux using electron beam currents from a cathode array formed on the window through which the radiation will exit the source. The source can be made in formats which are compact or flat compared with prior art radiation sources. X-ray flux produced by the source can be used for such purposes as radiation imaging, sterilization, decontamination of biohazards or photolithography.

Abstract: An X-ray tube for generating two focal spots displaced with respect to each other and a medical device using such X-ray tube are proposed. The X-ray tube (1) comprises a cathode (7) and an anode (9) wherein the cathode (7) comprises a first electron emitter (15) adapted for emitting a first electron beam (17) for generating a first focal spot (25) on the anode (9) and a second electron emitter (19) for emitting a second electron beam (21) for generating a second focal spot (27) on the anode (9). Therein, each electron emitter (15, 19) comprises an associated switchable grid (37, 39) for blocking the respective emitted electron beam (17, 21). In order to realize a desired displacement of the first and second focal spots (25, 27) in a y-direction, the first and second electron emitters (15, 19) may be displaced in the z-direction. Due to the focal spots (25, 27) being displaced in y-direction, an overall resolution of for example a high quality CT scanner may be significantly enhanced.

Abstract: An electron source for an X-ray scanner includes an emitter support block, an electron-emitting region formed on the support block and arranged to emit electrons, an electrical connector arranged to connect a source of electric current to the electron-emitting region, and heating structure arranged to heat the support block.

Abstract: A cathode assembly for an x-ray tube. In one example embodiment, a cathode assembly includes a cathode head, a filament, and first and second focusing tabs. The cathode head defines a recess having first and second open ends, a slot within the recess, and first and second tab stops within the recess. The filament is positioned within the slot. The first focusing tab is positioned in the first open end of the recess abutting the first tab stop. The second focusing tab is positioned in the second open end of the recess abutting the second tab stop.

Abstract: An industrial X-ray tube formed by accommodating a cathode and anode in a container having an evacuated interior, in which electrons emitted from the cathode are caused to strike the anode and X-rays are emitted from the anode. The cathode is formed from graphite. The graphite is a layered crystal obtained by layering a plurality of carbon hexagonal planes. The graphite is cut based on crystal axes of the carbon hexagonal planes. The resulting cut surface is caused to function as an electron-emitting surface. For example, directions of an a- and b-crystal axis may be set so as to be arbitrary between each of the layers of the carbon hexagonal planes, the graphite may be cut along a surface parallel to the c-axis, and the resulting cut surface may be caused to function as an electron-emitting surface. The graphite may also be cut along a surface orthogonal to the c-axis.

Abstract: Embodiments of the invention provide a novel, low-power X-ray tube and X-ray generating system. Embodiments of the invention use a multichannel electron generator as the electron source, thereby increasing reliability and decreasing power consumption of the X-ray tube. Unlike tubes using a conventional filament that must be heated by a current power source, embodiments of the invention require only a voltage power source, use very little current, and have no cooling requirements. The microchannel electron generator comprises one or more microchannel plates (MCPs), Each MCP comprises a honeycomb assembly of a plurality of annular components, which may be stacked to increase electron intensity. The multichannel electron generator used enables directional control of electron flow. In addition, the multichannel electron generator used is more robust than conventional filaments, making the resulting X-ray tube very shock and vibration resistant.

Abstract: An electron emitter assembly, and methods of assembly, is disclosed. The emitter assembly includes an electron emitter that is secured to a support device in a manner such that the emitter is substantially thermally isolated from the support device.