Abstract: A radiation source is disclosed comprising a source of charged particles that travel along a path. Target material lies along the path to generate radiation upon impact by the beam. A magnet is provided to deflect the beam prior to impacting the target. The magnet may generate a time-varying magnetic field or a constant magnetic field. A constant magnetic field may be varied spatially across the beam. The magnet may be an electromagnet or a permanent magnet. In one example, deflection of the beam results in impact of the beam on the target along a plurality of axes. In another example, portions of the beam are differentially deflected. The source may thereby irradiate an object to be scanned with more uniform radiation. The charged particles may be electrons or protons and the radiation may be X-ray or gamma ray radiation, or neutrons. Scanning systems incorporating such sources, methods of generating radiation and methods of examining objects are disclosed, as well.

Abstract: An x-ray tube has a stationary vacuum housing, in which are arranged an electron-emitting cathode and a ring anode with an impact surface on which the electron beam, accelerated by an electrical field, is incident, as well as a deflection system to focus and deflect the electron beam. The ray exit window of the x-ray tube is round, lies in the plane perpendicular to the central axis of the x-ray tube, and terminates one side at the vacuum housing. The impact surface of the ring anode is beveled and is aligned to the ray exit window. A diaphragm is provided in front of the ray exit window that defines a circular opening for the x-ray radiation. The ring anode is surrounded by an annular anode cooling arrangement.

Abstract: An X-ray inspection system includes an X-ray source that generates more than one beam defining an inspection plane, the beams being substantially parallel to each other; an X-ray detector having a plurality of detector arrays, each of which is aligned with one of the beams, and structure for supporting an object between the X-ray source and the X-ray detector. The X-ray source includes an electron gun and a device for steering an electron beam generated by the gun to multiple focal spots on a target.

Abstract: An X-ray emission device and method for a radiology apparatus comprises a cathode and a rotating anode, the anode being provided with a roughly cylindrical surface. The device forms a beam of electrons that bombards a portion of the roughly cylindrical surface of the anode that constitutes the focal point of emission of the X-rays. The position of the focal point of the anode relative to a reference position is dynamically controlled.

Abstract: A system and method for delivering radiation that comprises a source for creating an electron beam, a system that focuses the electron beam and then deflects the beam such that the beam is swept across a first target as an arbitrary pattern. The arbitrary pattern on the first target is given an additional intensity modulation. Thereafter, a lens focuses the arbitrary pattern of electrons from the first target onto a second target.

Abstract: By arranging for a collection of different materials to be used as x-ray targets in a single x-ray generator tube, an X-ray generator that can transmit a collection of unique x-ray spectra is produced according to one embodiment of the present invention. Spectrum selection can be accomplished by electronic means (with great speed) by deflecting an electron beam by means of electric fields, magnetic fields, and any combination of the two.

Abstract: An X-ray inspection system is provided comprising an X-ray source which includes an electron gun and beam steering means for alternately directing the electron beam from the gun in a first direction wherein the beam strikes the anode to produce a beam of X-rays which exits the X-ray source, and in a second direction wherein no significant X-ray flux exits the X-ray source. An X-ray detector and means for reading the detector are also provided. The beam steering means and the detector reading means are coordinated so that the detector output is read during a period when no significant X-ray flux exits the source. A method for operating the X-ray inspection system is also provided.

Abstract: In a method and a device for setting the focal spot position of an X-ray tube the focal spot position is regulated as a controlled variable by a closed loop regulation circuit. A deflector deflects the electron beam of the X-ray tube depending on a deflection signal, a deflection closed loop regulator generates the deflection signal depending on a focal spot position signal. A measurement arrangement measures a focal spot position signal.

Abstract: An X-ray inspection system is provided comprising an X-ray source which includes an electron gun and beam steering means for alternately directing the electron beam from the gun in a first direction wherein the beam strikes the anode to produce a beam of X-rays which exits the X-ray source, and in a second direction wherein no significant X-ray flux exits the X-ray source. An X-ray detector and means for reading the detector are also provided. The beam steering means and the detector reading means are coordinated so that the detector output is read during a period when no significant X-ray flux exits the source. A method for operating the X-ray inspection system is also provided.

Abstract: A personnel x-ray inspection system includes an electron source that provides a pencil beam of electrons. An electromagnet assembly receives the pencil beam of electrons and directs the beam of electrons along a line to form a scanning redirected beam under the control of a scan command signal. The scanning redirected beam strikes a target and generates a cone of x-rays that moves along a target line as a result of the scanning redirected beam. A collimator receives the scanning cone of x-rays and generates a collimated traveling pencil beam, which is directed to a person under inspection. A moving platform translates the person under inspection through the collimated traveling pencil beam. A backscatter detector detects backscattered x-rays, and provides a backscattered detected signal indicative thereof. A system controller provides the scan command signal, and also receives and processes the backscattered detected signal.

Abstract: A scanning electron beam computed tomographic system is provided with a sub-collimation system that passes X-rays emitted by a beam spot formed by an electron beam that is scanned across an X-ray emitting target, which X-rays would not otherwise reach an object under X-ray examination with the system. The sub-collimation system includes phantom-like objects that cause X-rays to be blocked, or passed, through to X-ray detectors depending primarily upon the beam spot position and, secondarily, on the beam-spot shape. Detector output signals may be used in real-time to control at least one characteristic of the electron beam-spot in a closed-loop correction system.

Abstract: A method and apparatus are disclosed for reducing variation in a spot size of an electron beam at a target due to multipole aberrations in an electron beam tomography (EBT) scanner. A magnitude of a DC voltage applied to a positive ion electrode (PIE) within the EBT scanner is adjusted and an orientation of a non-circular aperture of the PIE is aligned with respect to the electron beam. A profile of the spot size is monitored while adjusting the magnitude of the DC voltage and while aligning the orientation of the non-circular aperture of the PIE until the variation in the spot size is sufficiently reduced.

Abstract: A medical examination installation has an MR system and an X-ray system that has an X-ray radiator with an X-ray tube and a solid-state X-ray image detector for producing X-ray exposures. The X-ray system has sensors for the acquisition of the location dependency of the stray field of the MR system in the three spatial axes, and coils for compensation of the stray field, and a computer that uses the output signal of the sensors to calculate a current for the coils which cause the stray field to be reduced in the region of the electron beams of the X-ray tube.

Abstract: A miniaturized radiation device, having a support member in the form of a flexible sheet, and a circuit pattern of electrical contact pads and interconnecting conductor lines or leads provided on said support member. The pads are interconnected via said patterned lines. There is also a plurality of radiation chips electrically connected to selected ones of said pads. Preferably the device is wrapped around a core member, that may be a wire, such that the assembly is suitable for the insertion into a living body for the controlled administration of radiation at a therapy location.

Abstract: An x-ray tube having sensors, magnets, and/or active compensation means operatively coupled thereto or integrated therein for aligning its electron beam with external magnetic field. Permanent magnets positioned behind the anode and cathode respectively or electromagnets are used to produce a strong, properly aligned internal magnetic field. The x-ray tube is thus less sensitive to other magnetic fields that are not parallel to the anode-cathode axis. The x-ray tube can be mounted in a manner that it can pivot, allowing it to move and align itself. The x-ray tube can also be mounted such that a torque can be sensed. This sensed mechanical force is then used as an input to determine current applied to electromagnetic coils arranged to oppose transverse magnetic field.

Abstract: A cathode assembly (18) for an x-ray tube (1) includes a base (60) to which a filament (70) is mounted. A pair of deflectors (82, 84) are carried by the base for deflecting a beam (A) of electrons generated by the filament. Metal tubes (130, 132) are mounted in bores (106) of insulator blocks (104, 105). Metalized ends (150) of the insulator blocks are brazed into bores (122) in the base. A rod (130, 132) attached to the deflector is slid into the tube and the deflector's position and alignment are gauged and accurately set. The rod and tube are crimped to set the deflector position then welded.

Abstract: A system for inspecting the contents of a container is provided. The system includes a first source for emitting sequential beams of penetrating electromagnetic radiation from a target in a first set of substantially parallel directions, a conveyor for moving the container relative to the first source, a first detector for detecting the penetrating radiation after interaction with the contents of the container and generating a first set of signals corresponding to each of the substantially parallel directions and a controller for characterizing the contents of the container based at least on the first set of signals. The first detector may be a scatter detector. Similarly, the first detector may be a transmission detector.

Abstract: A cooling system for use with high-powered x-ray tubes. The cooling system includes a reservoir containing liquid coolant, in which the high-powered x-ray tube is partially immersed. In general, the liquid coolant is cooled and then circulated through the reservoir by an external cooling unit. The cooling system also includes a shield structure attached to the vacuum enclosure of the high-powered x-ray tube and disposed substantially about the aperture portion of the vacuum enclosure, thereby defining a flow passage proximate to the aperture portion. Liquid coolant supplied by the external cooling unit enters the flow passage by way of an inlet port in the shield structure. After passing through the flow passage and transferring heat out of the aperture portion, the liquid coolant is discharged through an outlet port in the shield structure and enters the reservoir to repeat the cycle.

Abstract: A field emission array electron source (12) is used to generate an electron beam in a x-ray generating device (10). The field emission array operates at room temperature and has a life expectancy in excess of 12,000 hours and provides a robust, efficient emitter for generating an electron beam in a x-ray generating device cathode (10).

Abstract: The invention provides a scheme in accordance with which a linear accelerator may be operated in two or more resonance (or standing wave) modes to produce charged particle beams over a wide range of output energies so that diagnostic imaging and therapeutic treatment may be performed on a patient using the same device. In this way, the patient may be diagnosed and treated, and the results of the treatment may be verified and documented, without moving the patient. This feature reduces alignment problems that otherwise might arise from movement of the patient between diagnostic and therapeutic exposure machines. In addition, this feature reduces the overall treatment time, thereby reducing patient discomfort.

Abstract: The origin of a cone or fan beam of B, &ggr;, or x radiation is moved in a continuous path such as a circle or is stepped among a two-dimensional grid of preselected points. The cone beam of radiation passes through a patient (14) in an imaging region (12) and is detected by a detector array (16). A data collection circuit (20) samples the detector array to generate radiation intensity sub-images. A circuit (56) monitors the shifting of the focal spot and controls an image shifting circuit (58) to shift physical coordinates of the sampled sub-image analogously. A sub-imaging combining circuit (60) interleaves or otherwise combines spatially shifted sub-images. In one embodiment, the combined sub-images forms a higher resolution composite image representation. In another embodiment, a plurality of combined, spatially shifted sub-images are collected at angularly offset orientations around the subject and are reconstructed into a higher resolution composite image representation.

Abstract: An X-ray generator, an X-ray inspector and an X-ray generation method capable of automatically focusing an energy beam, such as an electron beam for generating an X-ray, on a target are provided. The generation, inspector and the method have been developed by turning an attention on the fact that convergence conditions of an electron beam has a close relationship with a temperature on a surface of an X-ray tube target. The method comprises the steps of measuring the temperature changes at real time by a temperature sensor 14 and automatically controlling a current value of a focusing coil 6.

Abstract: The invention provides a scheme in accordance with which a linear accelerator may be operated in two or more resonance (or standing wave) modes to produce charged particle beams over a wide range of output energies so that diagnostic imaging and therapeutic treatment may be performed on a patient using the same device. In this way, the patient may be diagnosed and treated, and the results of the treatment may be verified and documented, without moving the patient. This feature reduces alignment problems that otherwise might arise from movement of the patient between diagnostic and therapeutic exposure machines. In addition, this feature reduces the overall treatment time, thereby reducing patient discomfort.

Abstract: An apparatus and method for generating electronically steerable beams of sequential penetrating radiation. Charged particles from a source are formed into a beam and accelerated to a target. Electromagnetic radiation generated by the target is emitted with an angular distribution which is a function of the target thickness and the energy of the particles. A beam of particles is produced by allowing the radiation to exit from an apparatus through a collimator proximal to the target. The direction of the beam is determined by the point of radiation production and the corresponding array of transmission regions of the collimator.

Abstract: A hood electrode attached to a tip portion of a target is provided with an electron passage port widening on the side opposite from an x-ray emitting window, so that electrons emitted from an electron gun are made incident on the front end face of a target at a position on the x-ray emission side, whereby the distance between the x-ray generating position and the x-ray emitting window can be shortened.

Abstract: A method and apparatus for producing a scanned beam of penetrating radiation. A beam of particles illuminates a portion of a target, the illuminated portion comprising a focal spot having a centroid. Illumination of the target creates a beam of penetrating radiation such as x-rays. The beam of particles is swept across the target in such a manner that the centroid of the focal spot lies on a line defined by the instantaneous direction of the beam of penetrating radiation as defined, in turn, by a collimating path.

Abstract: The invention relates to an X-ray tube whose cathode arrangement includes a flat electron emitter that is provided with openings. An electrode is arranged on the side of the electron emitter that is remote from the anode of the X-ray tube; this electrode carries a negative potential relative to the electron emitter, which negative potential straightens the electron paths in front of the emitter. These steps result in a favorable ratio of the dimensions of the electron emitter to the dimensions of the focal spot formed on the anode by the emitted electrons.

Abstract: An x-ray tube has a vacuum housing containing a cathode arrangement that emits electrons and an anode having a target surface on which the electrons, accelerated by an electrical field and forming an electron beam strike in a focal spot, and having a quadrupole magnet system including a coil, for focusing and deflection of the electron beam. A control unit is connected to the quadrupole magnet system. The control unit is supplied with, or has stored therein various parameter sets of predetermined coil currents that can be activated, so that, dependent on the respective parameter set, the focal spot can be displaced discretely in azimuthal fashion onto particular locations of the target surface of the anode.

Abstract: A system of navigating a magnetic medical device within that part of a patient located within an operating region of the system, the system comprising magnets, and preferably electromagnets, arranged to provide a magnetic field sufficient to navigate the magnetic medical device within the operating region. There are preferably three magnetic coils arranged in mutually perpendicular planes such that their axes intersect in the operating region. The magnetic coils are sized and arranged so that a patient can easily access the operating region to allow virtually any portion of the patient to be positioned within the operating region. The openness of the magnetic system allows access to the operating region by a bi-planer imaging system.

Abstract: The present invention provides methods for real-time measurement of motion of an object such as a portion of a patient in real-time through the use of harmonic phase (HARP) magnetic resonance imaging. This is accomplished by employing certain tagging protocols and imaging protocols. The imaging may be accomplished in two-dimension or three-dimension. In one embodiment, first and second tag pulse sequences are employed to provide two-dimensional pulse strain images. In another embodiment, a first tag pulse sequence is employed to determine a first harmonic phase image and a second tag pulse sequence is employed to determine a second harmonic phase image which is combined with the first image to create tagged images of circumferential and radial strains with third and fourth tag pulse sequences being employed to create images which are combined to establish longitudinal strain and thereby provide a three-dimensional strain image.

Abstract: X-ray tube with flying focus has a magnet system for deflecting and focusing the electron beam, whereby the magnet system including a carrier that is constructed as an iron yoke and that has four pole projections that are arranged around the axis of the electron beam offset from one another by 90°, on which two pairs of coils (z-coils and &phgr;-coils) are arranged so as to be offset from one another 90°. The individual coils of each pair supplied with a common high-frequency alternating current that deflects the electron beam in the &phgr;-and z-directions, respectively, in a pulsed manner.

Abstract: A hand holdable inspection device for three-dimensional inspection of a volume distal to a surface. The inspection device has a hand-holdable unit including a source of penetrating radiation for providing a beam of specified cross-section and a detector arrangement for detecting penetrating radiation from the beam scattered by the object in the direction of the detector arrangement and for generating a scattered radiation signal. Additionally, the inspection device has a controller for characterizing the volume based at least on the scattered radiation signal. The detector arrangement includes one or more backscatter detectors that may be disposed asymmetrically with respect to the beam and at differing displacements with respect to the surface.

Abstract: An X-ray radiator with a rotating bulb X-ray tube, with an allocated deflecting magnet system having at least one current-supplied coil for generating a magnetic deflecting field, has a circuit for tapping at least one reference signal representative of the high voltage existing at the X-ray tube. The coil current is adjusted by a control unit depending on this reference signal.

Abstract: An x-ray radiator has an x-ray tube with a deflection arrangement that deflects the electron beam of the x-ray tube dependent on a control signal such that the position of the focal spot on the anode corresponds to a reference position changing as a function of time. A detector acquires the actual position of the focal spot and a control unit is supplied with the actual value signal and a reference signal and generates the control signal.

Abstract: An X-ray tube 1 includes spacer 8 which is cylindrical so it does not block electrons 80 directed from a grid electrode 72 toward a focusing electrode 25, and which has one end 8b fixed to the grid electrode 72 and the other end 8c abutting against the focusing electrode 25. The distance between the grid electrode 72 and focusing electrode 25 is set to a predetermined distance by the spacer 8.

Abstract: A variable spot size x-ray tube comprises a cathode having an electron emitting surface providing an electron beam that travels essentially along the tube axis of symmetry to an anode. The anode, spaced from the cathode, includes a target, the front surface of which is disposed at an oblique angle with respect to the axis of symmetry. The potential of the anode is generally positive with respect to that of the cathode. The cathode is heated to a temperature at which electrons are emitted by the thermionic emission process. Current from the cathode can be controlled by varying the cathode temperature if the cathode is operated in the temperature limited region. The incident electron beam forms a spot on the target surface whereupon x-rays are produced in response to impingement of the electron beam on the target. The x-rays propagate outwardly from the target spot through a vacuum window to form a beam of x-radiation outside the x-ray tube.

Abstract: A modular X-ray radiator system includes at least one base X-ray radiator with a rotating bulb tube with a cathode that emits an electron beam, an anode, and an arrangement for variably deflecting the electron beam and for adjustment of the size of the focal spot of the electron beam on the anode, and a number of drive mechanisms of varying drive powers which can be selectively attached to one of the base X-ray radiators for the rotating of the rotating bulb tube.

Abstract: In a scanning electron beam CT system, a positive ion clearing electrode system is disposed within the CT system solenoid coil, and is operated from a single power source. Mounted coaxially about the electron beam, preferably the electrode system includes three sections, each having two electrode elements, one element being coupled to about −800 V to about −2 kV and the other element being grounded. Within the electrode system, the ratio between element diameter and electron beam diameter is substantially constant. Preferably elements are helically twisted about the beam axis. The electrode configuration cancels net quadrupole (focusing) and octopole (aberration-producing) fields. In the presence of electric discharge, essentially zero electron beam displacement and deflections occurs, and changes in focusing strength remain zero.

Abstract: A modular multistage accelerator for use in an X-ray treatment system includes a first 10 kV acceleration stage which houses an electron beam gun supplied with −50 kV of voltage. The modular multi-stage accelerator includes four additional 10 kV stages placed in series with the first stage to achieve a 50 kV accelerator overall. Each stage is shielded to prevent stray electrons from being propagated along the length of the drift tube. The triple point within each modular stage is recessed to significantly reduce the emission of stray electrons within each stage. Additionally, the beam current at the X-ray emitting probe of the X-ray source is measured by isolating the beam current to a beam current measuring circuit in electrical connection with a nulling junction node, wherein other currents within the circuit are nulled at the nulling junction node and the beam current flows to the beam current measuring circuit.

Abstract: The present invention, in one form, is a system for correcting thermal drift in an imaging system. More specifically, a correction algorithm determines an adjusted focal spot position based upon a first temperature focal spot position and a second temperature focal spot position. The adjusted focal spot position is utilized in the reconstruction process to correct for focal spot movement resulting from thermal drift.

Abstract: An X-ray source has an emitter for the production of an electron beam and an anode on which the electron beam strikes in an X-ray focal spot, and a magnet system that produces a dipole field and a quadrupole field that is superimposed on this dipole field, for deflecting and focusing the electron beam onto the anode. In addition, an arrangement is provided that operates together with the magnet system for the adjustment of the size of the X-ray focal spot. This arrangement, in order to set a desired size of the X-ray focal spot, adjusts the quadrupole field in so that the X-ray focal spot has a width corresponding to the desired size of the X-ray focal spot, and supplies to the magnet system a wobble signal that influences the dipole field, this wobble signal effecting a periodic displacement of the electron beam in a direction transverse to the extension of the width of the X-ray focal spot.

Abstract: Tuning, integrating, and operating an electron beam CT scanning system is simplified by using the fringe field from dipole magnets arranged as a chicane to focus the electron beam, thus replacing conventional quadrupole and solenoid coils. Preferably four "chicane" dipole magnets are series-coupled with the windings in the downstream deflection magnet, such that the chicane magnet X and Y coils are energized 90.degree. out of phase with the deflection magnet coils. The alternating current polarity in the chicane magnets creates an "S"-shaped electron beam trajectory that adequately uniformly focuses over the full cross-section of the electron beam. Winding the coils with a cosine distribution permits rotating the magnetic fields to change the azimuthal and deflecting planes of the electron beam, without disturbing the deflection angle and focusing properties.

Abstract: A miniature x-ray source utilizing a hot filament cathode. The source has a millimeter scale size and is capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature source consists of a compact vacuum tube assembly containing the hot filament cathode, an anode, a high voltage feedthru for delivering high voltage to the cathode, a getter for maintaining high vacuum, a connector for initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is fabricated from highly x-ray transparent materials, such as sapphire, diamond, or boron nitride.

Abstract: An x-ray tube has a cathode and an anode which are arranged in a vacuum housing, with an electromagnet for deflecting the electron beam traveling from the cathode to the anode. This electromagnet is formed by a C-shaped yoke with two legs that are connected to each other by a base section surrounded by a winding. Respective pole shoes with opposing pole faces are disposed at the ends of the legs. The electron beam passes between the two pole shoes as it propagates from the cathode to the anode. Each pole face has a width which does not exceed the width of its pole shoe.

Abstract: In an X-ray device which includes an X-ray tube (12) provided with means (15, 22, 23) for influencing the electron flow through the X-ray tube (12), a control voltage for the means for influencing the electron flow is customarily generated by means of a complex circuit which, because of its size, is not suitable to be accommodated within the protective tube housing. This has the drawback that the control voltage for the X-ray tube, usually of high voltage potential, must be supplied additionally to the high-voltage supply. Therefore, it is desirable to realize a simple generation means the control voltage which is suitable for accommodation in the protective tube housing. To this end, the invention proposes a piezoelectric transformer (21, 24, 25) for generating the control voltage for the X-ray tube. The invention also relates to a piezoelectric transformer which is particularly suitable for generating such a control voltage.

Abstract: An x-ray tube has a cathode and an anode arranged in a vacuum housing, wherein an electron beam emanating from the cathode is incident at a focal spot on the anode. An electromagnet is provided for deflecting the electron beam, this electromagnet having a U-shaped yoke with two legs connected by a base section with a winding surrounding the base section. The electron beam passes between the two legs. The yoke is formed by successively layered laminations disposed in respective planes disposed substantially perpendicularly to the propagation direction of the electron beam.

Abstract: An X-ray tube with a cathode and an anode arranged in a vacuum housing has an electromagnet for deflecting the electron beam emanating from the cathode and proceeding to the anode, the electromagnet having a yoke with two legs connected to one another by a base section, with a winding surrounding the base section. The base section with the winding is located outside the vacuum housing. The legs of the yoke of the electromagnet extend into the vacuum housing so that the electron beam proceeds between the two legs.

Abstract: An X-ray tube has a cathode and an anode that are arranged in a vacuum housing. For deflection of the electron beam propagating from the cathode to the anode, two electromagnets are provided, of which each having a U-shaped yoke with two arms connected with one another by a base segment, and comprises a winding surrounding the base segment. The respective end faces of the arms of the two yokes are arranged opposite one another so as to maintain an air gap. The magnetic poles positioned opposite one another have the same polarity. The electron beam proceeds through the opening limited by the two yokes.

Abstract: High energy scanning apparatus including a high voltage electrostatic generator and particle accelerator. A variable-trajectory electron beam is converted to a photon beam and collimated by a stationary collimator having a plurality of photon-passing slits. The stationary collimator produces a plurality of photon beams linearly and angularly displaced relative to each other in two dimensions. The photon beams are detected, thereby producing a plurality of preselected images including stereoscopic images. Also disclosed is a method of using the apparatus.

Abstract: An x-ray computed tomography apparatus with electronic scanning of a ring-shaped anode has a solenoid coil for space-charge compensation which allows access to the anode. The solenoid coil is constructed of multiple parts so that a connector part can be released from a base part and the anode is thereby made accessible.