Abstract: An electron beam generating apparatus for generating a plurality of electron beams, which includes: a plurality of cathodes for generating thermoelectrons; a cathode power supply unit for applying negative voltage to the cathodes so as to emit the thermoelectrons from the cathodes; a plurality of grids, which correspond to the plurality of cathodes respectively, for focusing the thermoelectrons emitted from each of the plurality of cathodes, and shaping the plurality of electron beams; and an insulator on which the plurality of cathodes and the plurality of grids are attached.

Abstract: A system for delivering therapeutic radiation, such as x-rays, to a treatment region includes a plurality of individually controllable therapeutic radiation sources. The therapeutic radiation sources are selectively and moveably disposed along one or more axes, or upon a two-dimensional surface, or within a three-dimensional volume, so as to form a one-dimensional or a multi-dimensional array. Each therapeutic radiation source includes an electron source for emitting electrons, and an associated target element adapted to emit therapeutic radiation in response to incident electrons. In one embodiment, each therapeutic radiation source is coupled to a distal end of an associated optical delivery structure, which is adapted to direct a beam of optical radiation to impinge upon a surface of the electron source so as to cause emission of electrons therefrom.

Abstract: An X-ray tube includes a substantially cylindrical rotor having an anode target fixed thereto, a substantially columnar stationary shaft coaxially arranged inside the rotor with a bearing gap, a dynamic slide bearing having helical grooves and formed between the rotor and the stationary shaft, and a metal lubricant supplied to the grooves and to the gap. An axial bore is formed in the shaft to extend in the longitudinal direction of the shaft, and an insertion rod is inserted into the axial bore such that a space extending in the longitudinal direction of the shaft is formed between an inner circumferential surface of the axial bore and an outer circumferential surface of the insertion rod. The space acts as at least one lubricant reservoir that is configured to store the metal lubricant.

Abstract: An X-radiation source can comprise an electron emission layer and an anode layer. In an embodiment the anode layer may be no more than approximately 1000 microns from the emission layer or include an anode region that laterally surrounds a hole extending through the anode layer. In one embodiment, a plurality of electron emission tips, extraction gate electrodes and anode regions may be used. When the anode regions comprise different materials, a plurality of wavelengths may be emitted. In another embodiment, a monolithic structure can be formed using processing operations similar to those used in conventional semiconductor device manufacturing. The X-radiation source can be relatively small and may have uses in applications with confined spaces, such as medical applications.

Abstract: An X-ray tube comprising an anode having a target surface radiating X-rays from a position of an X-ray focal spot by impingement of an electron beam, a focusing electrode and cathodes. The focusing electrode has a bottom portion positioned facing the target surface of the anode and most remote from the X-ray focal spot, at least one inclined wall surface obliquely ascending from the bottom portion in the direction of the anode, and substantially rectangular focusing recesses formed at the inclined wall surface. Each of the cathodes emits electron beams, positioned respectively in the focusing recesses of the focusing electrode. The focusing recess has first and second corners which curve from at least one end wall facing the end of the cathode to two side walls along the direction of the longer side of the cathode, and the first corner located remote from the bottom portion is gentler than the second corner located adjacent to the bottom portion with reference to condition of curving.

Abstract: An x-ray tube (10) includes a body (16) defining a vacuum envelope. A plurality of anode elements (18) each defining a target face are rotatably disposed within the vacuum envelope. Mounted within the vacuum envelope, a plurality of cathode assemblies (22) are each capable of generating an electron stream (36) toward an associated target face. A filament current supply (32) applies a current to each of the cathode assemblies, and is selectively controlled by a cathode controller (34) which powers sets of the cathodes based on thermal loading conditions and a desired imaging profile. A collimator (C) is adjacent to the body and defines a series of alternating openings (42) and septa (44) for forming a corresponding series of parallel, fan-shaped x-ray beams or slices (46).

Abstract: Methods for extending the life of an X-ray tube having at least two filaments which are individually energizable in which the filaments are successively energized either for a predetermined number of exposures or based on a predetermined passage of time, and methods for predicting imminent failure of still functioning filaments.

Abstract: The rotary cathode X-ray tube equipment of present invention is constructed so as to permit radiation of X-ray from all directions with respect to the whole circumference of a subject, and is used for x-ray CT. The equipment of the invention is constructed to prevent an X-ray radiation window 40 of a low strength from being influenced by atmospheric deformations of a vacuum vessel 1 or by machining and assembling errors, for example by using a joint portion disposed between the X-ray radiation window and an inner ring and having both a surface perpendicular to a rotational axis of a rotary member and a cylindrical surface parallel to the rotational axis, a face seal formed on the surface of the joint portion perpendicular to the rotational axis, and an axial seal formed on the cylindrical surface of the joint portion parallel to the rotational axis.

Abstract: The rotary cathode X-ray tube equipment of the present invention is constructed so as to permit radiation of X-ray from all directions with respect to the whole circumference of a subject, and is used for x-ray CT. The equipment of the invention is constructed to prevent an X-ray radiation window 40 of a low strength from being influenced by atmospheric deformations of a vacuum vessel 1 or by machining and assembling errors, for example by using a joint portion disposed between the X-ray radiation window and an inner ring and having both a surface perpendicular to a rotational axis of a rotary member and a cylindrical surface parallel to the rotational axis, a face seal formed on the surface of the joint portion perpendicular to the rotational axis, and an axial seal formed on the cylindrical surface of the joint portion parallel to the rotational axis.

Abstract: The rotary cathode X-ray tube equipment of the present invention is constructed so as to permit radiation of X-ray from all directions with respect to the whole circumference of a subject, and is used for x-ray CT. The equipment of the invention is constructed to prevent an X-ray radiation window 40 of a low strength from being influenced by atmospheric deformations of a vacuum vessel 1 or by machining and assembling errors, for example by using a joint portion disposed between the X-ray radiation window and an inner ring and having both a surface perpendicular to a rotational axis of a rotary member and a cylindrical surface parallel to the rotational axis, a face seal formed on the surface of the joint portion perpendicular to the rotational axis, and an axial seal formed on the cylindrical surface of the joint portion parallel to the rotational axis.

Abstract: An x-ray tube has an anode whose target area is divided into regions formed of different materials, whereby focal spots of different size can be optionally generated in each of the regions. The focal spots belonging to one region are respectively generated at different locations but all focal spots are generated so close together that the focal position is essentially the same for all focal spots. An operating method for such an x-ray tube is also disclosed.

Abstract: The rotary cathode X-ray tube equipment of the present invention is constructed so as to permit radiation of X-ray from all directions with respect to the whole circumference of a subject, and is used for x-ray CT. The equipment of the invention is constructed to prevent an X-ray radiation window 40 of a low strength from being influenced by atmospheric deformations of a vacuum vessel 1 or by machining and assembling errors, for example by using a joint portion disposed between the X-ray radiation window and an inner ring and having both a surface perpendicular to a rotational axis of a rotary member and a cylindrical surface parallel to the rotational axis, a face seal formed on the surface of the joint portion perpendicular to the rotational axis, and an axial seal formed on the cylindrical surface of the joint portion parallel to the rotational axis.

Abstract: A toroidal x-ray tube (I) is supported and selectively positioned by a gantry (II). The x-ray tube includes a toroidal housing (A) in which a rotor (30) is rotatably mounted. One or more cathodes (C) are mounted on the rotor for generating an electron beam which strikes an anode (B) to generate a beam of x-rays which passes through a window (20) and strikes an annular ring of detectors (160). A grid bias control circuit (100) selectively applies a continuously adjustable bias to a grid (36) for regulating the electron current, hence the intensity of the x-ray beam. A scintillating optical fiber (110) extends around the exterior of the window. The scintillation optical fiber includes fluorescent dopant (116) which convert a very small fraction of the x-rays into optical light which is transmitted along the fibers to an opto-electric transducer (118). The opto-electric transducer is connected with the grid bias control circuit.

Abstract: A toroidal x-ray tube (I) is supported (II) for rotation about a horizontal axis (170), translation along a vertical axis (172), and translation along a horizontal axis (174). The x-ray tube includes a toroidal housing (A), an annular anode (B), and a cathode (0) which rotates a beam of electrons around the annular anode. A plurality of parallel connected voltage sources (90.sub.1, 90.sub.2, . . . , 90.sub.n) provide a sufficiently high bias voltage between the electron source and the anode that x-rays are generated. The x-ray beam passes through a compensator crystal (62), an annular window (20), a collimator (132), through a subject received in a central bore (26) of the x-ray tube, and impacts an arc segment of radiation detectors (130). The x-ray detectors are stationarily mounted outside of the plane of the annular window (FIGS. 2 and 7), nutate into the plane of the windows opposite of the origin of the x-ray beam (FIG. 6 ), rotate in part (FIG. 9 ) or rotate in full (FIG.

Abstract: A mammography X-ray tube providing increased X-ray intensity for shortening patient exposure times to eliminate motion artifacts. The cathode design permits superpositioning of electron beam from multiple filaments.

Abstract: An evacuated envelope (C) which is connected with an anode (A), has a cathode assembly (B) rotatably mounted inside. Magnets (44, 46) hold the cathode assembly stationary as the anode and envelope rotate. A ferrite core transformer (60) includes a ferrite core primary (66) stationarily mounted exterior to the envelope. A secondary (64) is mounted to the cathode assembly interior to the envelope. The secondary winding includes a ferrite core (70), a portion of which is surrounded by a ceramic, dielectric bobbin (76). The bobbin includes walls or ridges (78) which define a spiral groove (80) therearound in which an uninsulated electric wire (82) is received. The uninsulated electric wire is connected with a cathode filament (52). The primary winding has a ferrite core (90) that has about five times the cross section as the secondary ferrite core to compensate for a low, about 20%, coupling efficiency between the primary and secondary windings.

Abstract: An anode (A) closes one end of an evacuated envelope (C) and a cathode end plate (22) closes the other. A cathode assembly (B) is mounted on a bearing (40) in the evacuated envelope such that the envelope and cathode can undergo relative rotation. A motor (38) rotates the anode and envelope while a pair of magnets (44, 46) hold the cathode assembly stationary. Bearing (40) functions as a current path from a current source (72) to the primary windings of a transformer (58). Another bearing (94) provides a return current path from the transformer to the current source. The secondary windings of the transformer are connected with a cathode filament (52). The transformer enables a relatively low ampere current to pass through the bearings to limit cathodic damage to the bearings, yet provides sufficient amperage to the filament to cause thermionic emission.

Abstract: The invention relates to X-ray tubes. The cathode for an X-ray tube has two filaments associated with a deflecting and focusing device which comprises at least three metal parts which are electrically insulated from one another and which are raised to electrical voltages. First and second ones of the metal, parts are associated with a first filament, while the second metal part and a third metal part are associated with the second filament.

Abstract: A cathode assembly (B) including cathode filaments (52, 54) remain stationary in the interior of a rotating evacuated envelope (C). The cathode filaments generate a beam of electrons (12) which strike an annular anode surface (10) that rotates with the envelope to generate a beam of x-rays (14). Electrical power from an AC electrical source (62) is conveyed across a circularly cylindrical peripheral side wall (20) of the envelope by pairs of concentric capacitive ring members (64, 70); (66, 72). One of the cathode filaments is selected either with (i) reed switches (82, 84), (ii) by bringing a selected one of the filaments and the capacitor rings into resonance at the frequency of the AC electrical source with a switch (86) and inductance (88a, 88b), or (iii) with a third pair of annular capacitive members (100, 102).

Abstract: An X-ray computer tomography system with a stationary ring anode and a plurality of stationary electron sources for the construction of fast scan images from the inside of an object is improved in such a way that there is free access from both sides of the scan region, that the gantry unit can be tilted, and that the image quality which can be achieved is comparable to that of conventional tomography systems with mechanical motion of the anode. A plurality of electron sources are configured in proximity to the ring anode on a stationary ring, with each source being capable of sweeping its respective electron beam over a portion of the anode ring.

Abstract: An x-ray radiator has an elongated cathode for emitting an electron beam having an elongated cross section, the electrons of the electron beam being accelerated onto an anode for generating x-radiation. The cathode is formed by a geometrical member completely filled with electron-emitting material, and the material of the cathode contains at least one element from the group of rare earths and at least one element from the group of precious metals or boron.

Abstract: Diode for providing X-rays. A diode for generating X-rays is adapted for connection to a source of high electrical energy with the diode having a first end from which the X-rays are emitted, a second end, and axis extending between the ends. The diode includes a ring cathode connected to the electron source and an intermediate anode spaced from the cathode with at least a portion of this anode being disposed between the ring cathode and the diode first end. The intermediate anode decelerates electrons to cause the generation of X-rays emitted from the diode first end. The diode also includes an intermediate cathode disposed radially outwardly of the intermediate anode and connected to this anode. The diode further includes an inverse anode spaced from the intermediate cathode and positioned radially outwardly of the intermediate cathode and between the intermediate cathode and between the intermediate cathode and the diode second end.

Abstract: Omni-directional X-ray tube having a target which is at least partially surrounded by an annular window passed by the X-rays, the cathode and the electron optics and the targets being designed such that the radiation passing the window is sweeping a larger sector in the plane of the window. The cathode arrangement includes at least two electron sources with an associated electron optics. The formation of the electron optics and of the targets is such that for each electron optic a focal point is generated on the target and the radiation originating from the individual focal points are sweeping about adjacent subsectors which are approximately screened against each other to avoid an overlapping.

Abstract: A multitarget x-ray tube which generates a number of x-ray beams of different characteristics in any desired combinations and/or sequences and in which cross-talk is reduced and beam purity is enhanced. The tube can be used in applications such as elemental analysis of materials by x-ray fluorescence, in which a sample is excited with x-rays from a primary source and in response releases x-ray photons having energies characteristic of the elements present in the sample, and in applications in which it can replace a radioactive source.

Abstract: An X-ray is generated when thermoelectrons emitted from a cathode impinge upon an anode, and the X-ray thus generated is taken out from a window. The cathode has a surface formed with two grooves intersecting at a right angle with each other and two coil filaments are fitted thereinto. By selectively heating one of the two coil filaments, a region on the anode upon which the thermoelectrons impinge is changed, whereby one of point- and line-focusing X-rays is selectively taken out from the window provided at a portion slightly below the face of the anode and at a wall of a casing of an X-ray tube.

Abstract: An x-ray tube contains a plurality of filaments each with an associated focus cup control to allow it to change rapidly between discrete emission intensities. The cathode structure of the x-ray tube is constructed so that each filament is located in a separate focus cup structure. However, the focus cup structures are electrically isolated so that a separate bias potential can be applied to each focus cup structure. By separately biasing each focus cup structure, the emission from each of the filaments can be controlled independently.

Abstract: An X-ray tube comprises a generally cylindrical evacuated metal tube envelope having an anode rotatably mounted therein. [The interior of the tube envelope adjacent the anode is provided with ceramic insulation to prevent flashover.] The anode is rotated by an external variable speed DC drive motor magnetically coupled through the tube envelope wall to the rotating anode assembly. [The tube envelope wall includes ferrous segments which minimize the gap in the magnetic coupling while permitting a thick and strong tube envelope wall. A variable speed DC motor or a variable speed air motor may be employed to drive the anode. In preferred embodiments, the anode drive means is electromechanically clutched to the anode, whereby the drive means can be brought up to the desired anode speed and thereafter clutched to the anode, the drive means acting as a flywheel to bring the anode quickly up to speed. Electromagnets operating as clutches are also employed.

Abstract: An X-ray tube having two individually energizable cathode filaments. If a primary filament is shorted to a cathode cup, a switch mounted inside the tube housing is thrown to couple a second filament to a filament energization signal. This avoids the necessity in replacing the X-ray tube if the primary filament is shorted and lengthens the effective life of the X-ray tube.

Abstract: A stereoscopic x-ray tube has an evacuated housing with a motor-driven anode dish therein, as well as at least two cathodes. The cathodes are disposed for directing electrons onto two respective foci within at least one track of the anode dish. Each of the foci generates a beam of useful x-rays, the two beams alternating. The anode dish is divided into at least one pair of segments of identical size, each segment emitting x-rays of a different intensity, so that only one segment in each pair can emit useful x-rays. The cathodes are disposed such that their respective foci are spaced at an uneven multiple of the length of the track within a segment.

Abstract: In an X-ray tube comprising a rotating anode mounted on magnetic bearings, the flow of anode current within the tube takes place without any contact by means of a stationarily fixed hollow anode in which is placed a cathode coupled rotationally to the rotating anode. The hollow anode is associated with heating means and the cathode is heated by thermal radiation within the hollow anode.

Abstract: The invention provides a general purpose X-ray tube for stereography usable in the field of radiology. An X-ray tube of the invention comprises at least three independent cathodes, each allowing a source of an X-ray beam to be obtained. These sources are at different distances from each other, so as to form working pairs allowing stereographic pictures to be taken of a subject with different enlargement values.

Abstract: An X-ray lithography apparatus wherein a linear X-ray source is formed by line scanning a target with electron lines, a band-slit having slits which extend in the direction similar to the longitudinal direction of said linear X-ray source and a solar-slit having plural slits in the direction perpendicular to said band-slit are interposed between the X-ray source and a wafer in order to irradiate only the component which is substantially perpendicular to the surface of the wafer out of the X-ray generated from the linear source, and said wafer is made to move continuously or stepwise in respect of a rectangular region which is highly collimated in order to conduct X-ray transfer against a predetermined region.

Abstract: This invention relates to an electron gun assembly for use, for example, in x-ray lithography, which includes an electron emitter assembly, beam forming elements disposed adjacent the electron emitter assembly, a target plane disposed in spaced relationship with respect to the electron emitter assembly, a deflector disposed adjacent the path of the electrons emitted from the electron emitter assembly, a pseudoanode mounted in spaced relationship with respect to the deflector and to the electron emitter assembly and to the target plane, said electron emitter assembly being interposed between the pseudoanode and the target plane.

Abstract: In an exemplary embodiment, a housing of shielding material, surrounding the cathode coils, has an opening for the transmission of the stream of electrons to the anode. A device for effecting a relative movement between the housing and the cathode coils is present, by means of which one of the cathode coils is selectively capable of being covered. The cathode coils can be mounted on a holder which is pivotal about the x-ray tube longitudinal axis by means of electromagnets. The electromagnets can be connected to the output of the filament supply transformer, associated with the respective cathode coil, and a multiplex circuit can be provided for the transmission of the control signals.

Abstract: A high speed multiple section, computed-tomographic x-ray scanner is provided. The scanner utilizes a multiple-anode, scanning electron beam x-ray source to provide high speed scanning of sections of the body. No mechanical motion is involved.