Abstract: Disclosed herein is an apparatus for electromagnetic x-ray control. The apparatus comprises a thermionic filament, positioned at a first end of a micro-focus x-ray tube and configured to generate an electron stream. The apparatus also comprises an x-ray generation target, positioned within the micro-focus x-ray tube at a second end of the micro-focus x-ray tube, opposite the first end, to receive the electron stream and to generate x-rays in response to the electron stream impinging on the x-ray generation target. The apparatus further comprises an electromagnetic field element, configured to generate an electromagnetic field that receives the electron stream and operable to vary the electromagnetic field to redirect the electron stream, within the micro-focus x-ray tube, to impinge on the x-ray generation target at variable locations on the x-ray generation target. Each one of the variable locations corresponds to a different one of multiple variations of the electromagnetic field.

Abstract: A digital dental x-ray sensor device includes a rounded, three dimensional housing that lacks corners, edges, or other relatively sharp features that are known to cause discomfort when used in a patient's mouth. The rounded three dimensional housing can be spherical, ellipsoid, or any similar regular or irregular rounded shape, and can be formed by ensuring that all curves of a surface of the rounded three dimensional housing have a minimum radius that is sufficient to prevent features that can dig into a soft tissue of the inside of a patient's mouth.

Abstract: A system and method for the present invention requires use of a generator, in combination with a radiation unit, to radiate electromagnetic waveform energy onto a target tissue (i.e. a cellular structure). During radiation of the target tissue in accordance with a predetermined titration-like protocol, the influence of the waveform energy on the cellular structure is periodically monitored. The protocol is stopped when the cellular structure has been transformed or morphed into a desired phenotype.

Abstract: An X-ray generation apparatus includes an electron gun having a cathode emitting an electron beam, a first housing accommodating the electron gun, a target on which the electron beam emitted from the electron gun is incident, a second housing accommodating the target, and an electron passage extending between the first housing and the second housing and configured to transfer the electron beam from a first internal space of the first housing to a second internal space of the second housing. The electron passage includes a diameter-reduced end portion decreasing in diameter toward the target. The first housing is provided with a first exhaust flow path for evacuating the first internal space in the first housing. The second housing is provided with a second exhaust flow path for evacuating the second internal space in the second housing.

Abstract: A system and method for calibrating an X-ray tube is provided in which the X-ray tube includes an electronic storage medium associated with the X-ray tube on which calibration information for the X-ray tube is stored. The calibration information includes operating parameters for the focusing elements of the X-ray tube for desired focal spots, tolerance limits for variations in the focal spots and a number of gradient coefficient values corresponding to certain modulation transfer functions (MTF) for the X-ray tube that the imaging system can employ in an iterative manner to correct the operating parameters of the focusing elements to achieve the desired focal spot. This automatic iterative process significantly reduces the time required for the calibration of the X-ray tube. The system and method also employs scan sequencing to minimize the heat generated enabling the scans to be completed in a shorter amount of time than prior calibration processes.

Abstract: An imaging system (10) comprises a beam source (20), a detector unit (30), a beam limiting unit (40), and a control unit (50). The beam source (20) generates a beam (22) and projects it onto the detector unit (30), thus generating a radiated field (32) being limited by the beam limiting unit (40). The detector unit (30) provides image data as a result of the beam (22). The control unit (50) is configured to provide image data of a desired region of an object (60) by selecting a predetermined image field (34) of the detector unit. The control unit (50) is configured to determine a correction factor for a relative position and/or a relative orientation of the image field (34) with respect to the radiated field based on an orientation of the imaging system and to control the beam limiting unit as to reduce the cross-sectional area of the beam.

Abstract: A magnetic apparatus and a method of operating the magnetic apparatus can include a scanning electromagnet that redirects a beam of charged particles, a vacuum chamber that prevents the atmosphere from interfering with the charged particles; and, a parallelizing permanent magnet array for parallelizing the beam of charged particles. The parallelizing permanent magnet array can be located proximate to a target comprising a Bremsstrahlung target or an object that is being irradiated. The magnetic field of the scanning electromagnet can be variable to produce all angles necessary to sweep the beam of charged particles across the target and the parallelizing permanent magnet array can be configured from a magnetic material that does not require an electric current.

Abstract: According to one embodiment, an emitter comprise a base portion including an electron emission surface from which electrons are emitted, a pair of leg portions applying a voltage to the electron emission surface, and a rib portion formed by bending an edge of the base portion to a side opposite to the electron emission surface, on at least a part of an outline of the electron emission surface.

Abstract: Provided herein is a field emission device. The field emission device includes a cathode which is connected to a negative power supply and emits electrons, an anode which is connected to a positive power supply and includes a target material receiving the electrons emitted from the cathode, and a ground electrode which is formed to face the anode and has an opening through which the electrons emitted from the cathode pass. The ground electrode is grounded so that when an arc discharge occurs due to high voltage operation of the anode, electric charge produced by the arc discharge is emitted to a ground.

Abstract: A multiplexing x-ray fluorescence (MXRF) system and method are provided. The system can include a simple detector that counts x-rays with time resolution. A time-variable applied radiation source is used. The MXRF applied radiation source can produce an excitation spectrum with a peak average energy that grows with time and then recycles. Elemental identification can be achieved by time-correlating x-ray counts detected by the detector, with the time-variable applied radiation field. The system and method provide design flexibility for both commercial and NASA applications.

Abstract: Methods, systems, and related computer program products for processing and displaying computer-aided detection (CAD) information associated with medical breast x-ray images, such as breast x-ray tomosynthesis volumes, are described. An interactive graphical user interface for displaying a tomosynthesis data volume is described that includes a display of a two-dimensional composited image having slabbed sub-images spatially localized to marked CAD findings.

Abstract: Methods and apparatus are provided for performing back-reflection energy-dispersive X-ray diffraction (XRD). This exhibits extremely low sensitivity to the morphology of the sample under investigation. As a consequence of this insensitivity, unprepared samples can be analyzed using this method. For example, in a geological context, whole rock samples become amenable to analysis. A composite diffraction spectrum can be produced using information from different recorded spectra in different energy sub-ranges. The composite spectrum excludes fluorescence signals that would otherwise obscure the diffraction signals.

Abstract: According to some aspects, an x-ray apparatus for imaging and/or radiation therapy is provided, the x-ray apparatus comprises an electron source capable of generating electrons, at least one first target arranged to receive electrons from the electron source, the at least one first target comprising material that, in response to being irradiated by the electrons, emits broad spectrum x-ray radiation, at least one second target arranged to receive at least some of the broad spectrum x-ray radiation, the at least one second target comprising material that, in response to irradiation by broad spectrum x-ray radiation from the first target, emits monochromatic x-ray radiation, and at least one detector positioned to detect at least some of the monochromatic x-ray radiation emitted from the at least one second target.

Abstract: An improved cathode assembly is disclosed. The improved cathode assembly provides a deep channel for holding filament that enables generation of small focal spots, but is not limited in achieving larger focal spot sizes. The cathode assembly includes at least one deep channel and a filament arranged in a deep channel. The deep channel is configured in a cathode cup surface of the cathode assembly. The filament is arranged in the deep channel for enabling emission of electron beams from the cathode assembly.

Abstract: An X-ray tube is provided. The X-ray tube includes an electron beam source including a cathode configured to emit an electron beam. The X-ray tube also includes 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 further includes a gridding electrode disposed about a path of the electron beam between the electron beam source and the anode assembly. The gridding electrode, when powered at a specific level, is configured to grid the electron beam in synchronization with planned transitions during a dynamic focal spot mode.

Abstract: A radiographic apparatus includes a target array and an X-ray detecting unit. The target array includes a plurality of targets and a forward shielding member. The X-ray detecting unit includes a detecting portion. The X-ray detecting unit further includes a shielding portion extending toward an outer side of the detecting portion along an array direction in which the targets are arrayed.

Abstract: A radiographic apparatus including a target array and an X-ray detecting unit. The target array includes a plurality of targets and a forward shielding member. The forward shielding member includes a plurality of partitions. The X-ray detecting unit includes a detecting portion. The partitions each have sloping surfaces whose angles of inclination change along an array direction.

Abstract: An x-ray apparatus (1), has an electron beam source (2), a target (4), onto which the electron beam (3) is directed to form a focal spot (5; 5a, 5b) on the target (4), x-ray optics (6) for collecting x-rays emitted from the focal spot (5; 5a, 5b) to form an x-ray beam (8) and a sample position (9) at which the x-ray beam (8) is directed. The x-ray apparatus (1) further includes an electrostatic or electromagnetic electron beam deflection device (10) suitable for moving the focal spot (5; 5a, 5b) on the target (4). The extension of the focal spot (5; 5a, 5b) in any direction (x, y, z) is at least a factor of 1.5 smaller than the extension of the target (4). An x-ray apparatus is thereby provided with simplified alignment of the x-ray optics with respect to a microfocus x-ray source.

Abstract: In the present invention, a cathode assembly for an X-ray tube is provided including a cathode cup, a pair of emitters disposed within the cup and each configured to emit an electron beam therefrom and an electrode spaced from the pair of emitters and configured to affect the shape and/or intensity of the electron beams emitted by the pair of emitters. The electrode includes a rod extending across a central aperture defined within the electrode that enables the electrode to grid or focus the electron beam or beams emitted from the emitters using a bias voltage between +10 kV and ?10 kV.

Abstract: Disclosed herein are a high-voltage generator for an x-ray source, an x-ray gun, an electron beam apparatus, a rotary vacuum seal, a target assembly for an x-ray source, a rotary x-ray emission target, and an x-ray source. These various aspects may separately and/or together enable the construction of an x-ray source which can operate at energies of up to 500 kV and beyond, which is suitable for use in commercial and research x-ray applications such as computerized tomography. In particular, the high-voltage generator includes a shield electrode electrically connected intermediate of a first voltage multiplier and a second voltage multiplier. The electron beam apparatus includes control photodetectors and photo emitters having a transparent conductive shield arranged therebetween. The rotary vacuum seal includes a pumpable chamber at a position intermediate between high-pressure and low-pressure ends of a bore for a rotating shaft.

Abstract: Methods and apparatus are provided for performing back-reflection energy-dispersive X-ray diffraction (XRD). This exhibits extremely low sensitivity to the morphology of the sample under investigation. As a consequence of this insensitivity, unprepared samples can be analyzed using this method. For example, in a geological context, whole rock samples become amenable to analysis. A composite diffraction spectrum can be produced using information from different recorded spectra in different energy sub-ranges. The composite spectrum excludes fluorescence signals that would otherwise obscure the diffraction signals.

Abstract: The present disclosure provides a mobile back scattering imaging security inspection apparatus, comprising: a back scattering scanner (2), a detector (3), a controller (4), and a movable stage (1) configured to carry the back scattering scanner, the detector and the controller and being movable with respect to the object to be inspected; wherein the back scattering scanner is a distributed X-ray source comprising a plurality of target points (201), each of which is able to emit the ray beam individually, and wherein the back scattering scanner, the detector and the controller perform an imaging security inspection operation on the object to be inspected during moving along with the movable stage with respect to the object.

Abstract: Methods, systems, and related computer program products for processing and displaying computer-aided detection (CAD) information associated with medical breast x-ray images, such as breast x-ray tomosynthesis volumes, are described. An interactive graphical user interface for displaying a tomosynthesis data volume is described that includes a display of a two-dimensional composited image having slabbed sub-images spatially localized to marked CAD findings.

Abstract: The present invention relates to a radiographic imaging apparatus and a corresponding radiographic imaging method. The proposed apparatus comprises an X-ray source and a photon counting X-ray detector. The X-ray source comprises a rotary X-ray anode having a number of radial slits and a target layer provided on a surface of said rotary X-ray anode in between said radial slits for emitting X-ray radiation when hit by said electron beam. The said photon counting X-ray detector comprises a persistent current sensing and correction unit for sensing a persistent output current in a blanking interval during which no X-ray radiation is emitted by said X-ray source and for using the sensed persistent output current to correct a detector signal in a subsequent measurement interval during which X-ray radiation is emitted by said X-ray source.

Abstract: An X-ray tube includes a cathode, an anode, and a deflection device. The cathode and the anode generate an electron beam that is directed toward a target area of the anode to generate X-ray radiation through electrons of the electron beam impinging the target area. The deflection device controls the electron beam such that the electrons hit the anode at different focal spot positions. The deflection device provides gradual deflection for a stepless transition between monoscopic viewing and stereoscopic viewing. For monoscopic viewing, the X-ray radiation is generated from a single focal spot position. For stereoscopic viewing, the X-ray radiation is generated from two focal spot positions spaced apart in a first stereo-direction transverse to a viewing direction. The deflection device provides gradual deflection for a stereo focal spot position in a second stereo-direction, which is transverse to the first stereo-direction and the viewing direction.

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: Provided is an X-ray energy spectrum estimation method capable of reproducing, with high precision, information on an attenuation path to which an X-ray is irradiated, and performing, with high precision, reconstruction of an X-ray CT image by enabling high-precision estimation of spectrum of energy released from an X-ray source device. An energy spectrum estimation device (92) normalizes a response function, and calculates a modified efficiency matrix from the normalized response function, a detection efficiency matrix, and a measurement-system correction coefficient. The energy spectrum estimation device then calculates a particular result in accordance with a Bayesian estimation equation, without divergence, with use of the calculated modified efficiency matrix, the normalized modified efficiency matrix, and an attenuation characteristic curve obtained by a measurement circuit (30).

Abstract: An X-ray backscatter imaging system uses frequency modulated X-rays to determine depth of features within a target. An X-ray source generates X-ray radiation modulated by a frequency-modulated bias current. The X-ray radiation impinges upon and is backscattered from multiple depths within the target. A scintillating material receives the backscattered X-rays and generates corresponding photons. A photodetector, having gain modulated by the frequency modulation signal from the local oscillator, receives the photons from the scintillating material and generates an analog output signal containing phase delay information indicative of the distance travelled by the X-rays backscattered from multiple depths within the target. The analog output signal is sampled by an analog-to-digital converter to create a digital output signal. A computer processor performs a discrete Fourier transform on the digital output signal to provide target depth information based on the phase delay information.

Abstract: Embodiments are described for a method for using anti-aliasing hardware to generate a higher resolution image at the processing of a lower resolution image with anti-aliasing. A graphics image comprising allocating a buffer used in a multisample anti-aliasing process, wherein the allocated buffer has a dimension comprising a reduction in at least one of the width or height of an original dimension of an original buffer provided by the anti-aliasing hardware; rendering sampled image data to the allocated buffer at a sampling rate proportional to the reduction; and expanding the allocated buffer back to the dimension of the original buffer.

Abstract: An X-ray imaging system or radiographic imaging system includes a radiation generating apparatus and a radiographic imaging apparatus. An ionization chamber device is external to the radiographic imaging apparatus, for detecting a dose of the radiation transmitted through an object. Dose sensors are incorporated in the radiographic imaging apparatus, for detecting a dose of the radiation transmitted through the object. An exposure control unit is disposed with the radiation generating apparatus, for shutting off application of the radiation from the radiation generating apparatus according to a detection signal from the ionization chamber device or dose sensors. The ionization chamber device is communicably coupled with the radiation generating apparatus. An operating state of the ionization chamber device and dose sensors is acquired by monitoring, so failure of simultaneous inputting of their detection signals to the exposure control unit is prevented.

Abstract: The purpose of the present invention is to provide a stereo x-ray radiation device that is small and for which handling is simple. One cathode that functions as an emitter and two anodes that function as targets are disposed in a single straight-tube shaped vacuum vessel. The stereo x-ray generating device is characterized by the cathode being a cold cathode disposed in the center part of the vessel, the anodes being disposed each to one end of the vessel, and the spaces between the anodes disposed in the two ends of the vessel and the cathode being constituted such that the same can be moved closer or apart along the axial line of the vessel.

Abstract: An X-ray generator and an X-ray photographing apparatus including the X-ray generator generate characteristic X-rays. The X-ray generator includes an electron beam emission unit that emits electron beams; an electron beam guide unit, in which the electron beam emission unit is disposed, for condensing the electron beams and causing the electron beams to travel in a predetermined direction; and a target unit disposed to face the electron beam guide unit, and discharging X-rays when the electron beams collide with the target unit.

Abstract: An x-ray source is described. During operation of the x-ray source, an electron source emits a beam of electrons. This beam of electrons is focused to a spot on a target by a magnetic focusing lens. In response to receiving the beam of focused electrons, the target provides a transmission source of x-rays. Moreover, a repositioning mechanism selectively repositions the beam of focused electrons to different locations on a surface of the target based on a feedback parameter associated with operation of the x-ray source. This feedback parameter may be based on: an intensity of the x-rays output by the x-ray source; a position of the x-rays output by the x-ray source; an elapsed time during operation of the x-ray source; a cross-sectional shape of the x-rays output by the x-ray source; and/or a spot size of the x-rays output by the x-ray source.

Abstract: A two dimensional array distributed x-ray apparatus of this disclosure comprises: a vacuum box which is sealed at its periphery, and the interior thereof is high vacuum; a plurality of electron transmitting units arranged in one plane in a two dimensional array on the wall of the vacuum box; an anode having targets corresponding to the plurality electron transmitting unit arranged in parallel with the plane of the plurality of electron transmitting units in the vacuum box; a power supply and control system having a high voltage power supply connected to the anode, a filament power supply connected to each of the plurality of the electron transmitting units, a grid-controlled apparatus connected to each of the plurality of electron transmitting units, a control system for controlling each power supply; wherein the anode comprises: an anode plate made of metal and parallel to the upper surface of the electron transmitting unit; a plurality of targets arranged on the anode plate and disposed corresponding to the

Abstract: Apparatus and methods to control an electron beam of an x-ray tube are provided. One apparatus includes at least one of (i) a first switching unit having a voltage source and a pair of switches connected in series and configured to switch between open and closed positions to change an output voltage to engage or bypass the voltage source or (ii) a second switching unit connected to a voltage source and having a first pair of switches connected in series and a second pair of switches connected in series, wherein the first and second pair of switches are connected in parallel, and wherein the first and second pairs of switches are configured to switch between open and closed position to change an output voltage generated from the voltage source. The first and second switching units are connected in series and a third switching unit provided that is amplitude controllable.

Abstract: An x-ray beam control system includes a feedback control loop circuit having a modulation circuit. The feedback control loop circuit generates a control signal. A x-ray tube, has a filament response profile of tube current versus filament temperature that is non-linear. A compensation circuit receives the control signal and modifies the control signal according to a compensating function that is matched to the filament response profile. The modulation circuit receives the modified control signal and generates a drive signal. The x-ray tube receives the drive signal at a filament thereof, and outputs a tube current signal having a linear response to the control signal. The feedback control loop circuit receives the tube current signal.

Abstract: Provided herein are systems and methods for operating a traveling wave linear accelerator to generate stable electron beams at two or more different intensities by varying the number of electrons injected into the accelerator structure during each pulse by varying the width of the beam pulse, i.e., pulse width. The electron beams may be used to generate x-rays having selected doses and energies, which may be used for cargo scanning or radiotherapy applications.

Abstract: A segmented thermionic emitter is provided. The segmented thermionic emitter has, among other features, a plurality of segments substantially spanning an entire length of the thermionic emitter and aligned substantially parallel with one another. In one embodiment, the segmented thermionic emitter may allow milli-amp modulation of an X-ray tube at voltages less than approximately 2 kV.

Abstract: The present embodiments improve the radiation monochromy of an x-ray device with a control electrode for controlling a flow of electrons generated between a cathode and an anode. A correction voltage is generated in accordance with a correction function. This correction voltage is used for correction of a voltage applied between the anode and the cathode in terms of a constant voltage, even in the period of control using the control electrode. The voltage applied between the anode and the cathode is corrected with the generated correction voltage.

Abstract: An apparatus and method to generate distributed x-rays. A hot cathode of an electron gun is used in vacuum to generate electron beams having certain initial movement energy and speed. Periodic scanning is performed with the initial low-energy electron beams, which are thus caused to be reciprocally deflected. A current-limiting device is provided in the travel path of the electron beams along the direction of the reciprocal deflection. Through holes arranged in an array on the current-limiting device, only part of the electron beams targeting specific positions can pass to form sequential electron beam currents distributed in an array. These electron beam currents are accelerated by a high-voltage electric field to obtain high energy, bombard an anode target, and thus sequentially generate corresponding focus spots and x-rays distributed in an array at the anode target.

Abstract: This invention relates to an apparatus producing distributed X-ray, and in particular to a cathode control multi-cathode distributed X-ray apparatus, which produces X-ray that changes focal position in a predetermined order by arranging multiple independent hot cathodes and controlling cathodes in an X-ray source device, and a CT device having said X-ray apparatus.

Abstract: A multi-radiation unit includes: a multi-radiation tube which has a plurality of electron sources, a plurality of targets and an intermediate electrode having openings through which electrons emitted from the electron sources pass; a selection circuit that allows electrons to be emitted from a selected electron source selected from the plurality of electron sources; an intermediate electrode potential defining unit that defines a potential of the intermediate electrode; a storage unit that stores, for each of the plurality of electron sources, an electrostatic control condition of the intermediate electrode for obtaining a predetermined irradiated state of a target corresponding to the selected electron source; and a changing unit that changes, when electrons are emitted from the selected electron source, the electrostatic control condition of the intermediate electrode based on the electrostatic control condition stored in the storage unit for the selected electron source.

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: The present embodiments relate to off-focal X-ray radiation attenuation within X-ray tubes, for example X-ray tubes used in CT imaging. In one embodiment, an X-ray tube for off-focal X-ray radiation attenuation is provided. The X-ray tube includes a cathode, a target, and a magnetic focal spot control unit having at least one electromagnet encased in a resin loaded with X-ray attenuating material.

Abstract: A radiation inspection apparatus includes a radiation source, a measurement radiation detecting unit being a rectangle having a long side, and a reference radiation detecting unit that is disposed between the radiation source and an inspection target, the reference radiation detecting unit being disposed near a path of a radiation from the radiation source to the measurement radiation detecting unit not to interrupt the radiation from the radiation source to the measurement radiation detecting unit. An intensity of the radiation source are corrected by calculating a change value of the intensity and the intensity distribution from an output of the reference radiation detecting unit and by correcting the output of the measurement radiation detecting unit based on the change value.

Abstract: An electromagnetic wave having a phase velocity and an amplitude is provided by an electromagnetic wave source to a traveling wave linear accelerator. The traveling wave linear accelerator generates a first output of electrons having a first energy by accelerating an electron beam using the electromagnetic wave. The first output of electrons can be contacted with a target to provide a first beam of x-rays. The electromagnetic wave can be modified by adjusting its amplitude and the phase velocity. The traveling wave linear accelerator then generates a second output of electrons having a second energy by accelerating an electron beam using the modified electromagnetic wave. The second output of electrons can be contacted with a target to provide a second beam of x-rays. A frequency controller can monitor the phase shift of the electromagnetic wave from the input to the output ends of the accelerator and can correct the phase shift of the electromagnetic wave based on the measured phase shift.

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 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 apparatus and method for calibrating an x-ray tube include a computer programmed to acquire a starter voltage/current value corresponding to a width, a length, or a position of a target focal spot capable of being generated by the x-ray tube. The computer is programmed to generate an electron beam and to steer the electron beam based on the starter voltage/current value. The computer is also programmed to steer the electron beam based on a value adjusted from the starter voltage/current value. The computer is programmed to calculate a final voltage/current value that is configured to generate the width, length, or position of the target focal spot based on the starter voltage/current value and the adjusted starter voltage/current value.

Abstract: An electromagnetic wave having a phase velocity and an amplitude is provided by an electromagnetic wave source to a traveling wave linear accelerator. The traveling wave linear accelerator generates a first output of electrons having a first energy by accelerating an electron beam using the electromagnetic wave. The first output of electrons can be contacted with a target to provide a first beam of x-rays. The electromagnetic wave can be modified by adjusting its amplitude and the phase velocity. The traveling wave linear accelerator then generates a second output of electrons having a second energy by accelerating an electron beam using the modified electromagnetic wave. The second output of electrons can be contacted with a target to provide a second beam of x-rays. A frequency controller can monitor the phase shift of the electromagnetic wave from the input to the output ends of the accelerator and can correct the phase shift of the electromagnetic wave based on the measured phase shift.