Abstract: A magnet array (700) includes multiple magnet rings (711-720) and a frame. The multiple magnet rings are positioned along a longitudinal axis and coaxially with the longitudinal axis, wherein at least one (712, 713, 719) of the magnet rings possesses rotational symmetry and has both a finite component of magnetization along an azimuthal (?) coordinate, and a finite magnetization in a longitudinal-radial plane. The multiple magnet rings configured to jointly generate a magnetic field along a direction parallel to the longitudinal axis. The frame is configured to fixedly hold the multiple magnet rings in place.

Abstract: Devices, systems and methods for calibrating and operating an additive manufacturing system are disclosed. A calibration system for an electron beam additive manufacturing system having a plurality of electron beam guns includes a calibration probe positioned in a build chamber of the electron beam additive manufacturing system, a sensing device positioned to measure and acquire a response generated as a result of impingement of electron beams emitted from the plurality of electron beam guns on the calibration probe, the sensing device generating a response signal as a result of the measured and acquired response, and an analysis component communicatively coupled to the sensing device and programmed to analyze and evaluate the response signal.

Abstract: The present disclosure provides an inspection system and a method of stray field mitigation. The system includes an array of electron beam columns, a first permanent magnet array, and a plurality of shielding plates. The array of electron beam columns each includes an electron source configured to emit electrons toward a stage. The first permanent magnet array is configured to condense the electrons from each electron source into an array of electron beams. The first permanent magnet array is arranged at a first end of the array of electron beam columns. The plurality of shielding plates extend across the array electron beam columns downstream of the first permanent magnet array in a direction of electron emission. The array of electron beams pass through a plurality of apertures in each of the plurality of shielding plates, which reduces stray magnetic field in a radial direction of the array of electron beams.

Abstract: A magnet array (700) includes multiple magnet rings (711-720) and a frame. The multiple magnet rings are positioned along a longitudinal axis and coaxially with the longitudinal axis, wherein at least one (712, 713, 719) of the magnet rings possesses rotational symmetry and has both a finite component of magnetization along an azimuthal (?) coordinate, and a finite magnetization in a longitudinal-radial plane. The multiple magnet rings configured to jointly generate a magnetic field along a direction parallel to the longitudinal axis. The frame is configured to fixedly hold the multiple magnet rings in place.

Abstract: A method for manufacturing a magnet includes (1) a step of preparing three or more unmagnetized magnet materials of which magnetization easy axes are oriented in predetermined directions, and adhering the unmagnetized magnet materials with each other to make an assembly, and (2) a step of applying a curved pulse magnetic field to the assembly to magnetize the assembly, wherein in the step (2), the unmagnetized magnet materials are magnetized into magnet blocks, and an angle ? (where 0???180 degrees holds) formed by magnetization directions of at least a pair of magnet blocks adjacent to each other is in a range of 30 degrees to 120 degrees.

Abstract: An RF circuit for an electron beam device is formed with successive layers of fusible metal particles applied in layers and translated with respect to an electron beam. Segments of an electron device may be formed which include an open RF cavity at each end of the segment, which can be machined before the segments are brazed together. In one example, the electron beam device may have iron pole pieces assembled into the partially fused device to provide a magnetic circuit and support for subsequent layers of fused particles. The inner surfaces of the RF circuit structure may be smoothed using an etching or machining operation, and the segments may be brazed together to form a completed RF circuit structure with the magnetic pole pieces included in the monolithic structure segments.

Abstract: An undulator comprises at least M permanent magnet periods arranged sequentially in a transmission direction of electron beams, each of the permanent magnet periods comprises four rows of permanent magnet structures, in which each row comprises N rows of permanent magnet groups, and each row of the permanent magnet groups comprises K permanent magnet units, wherein M, N and K are natural numbers greater than or equal to 1; the four rows of the permanent magnet structures are pairwise matched, then relatively disposed on both sides of the transmission direction of electron beams, and are capable of forming at least one composite magnetic fields by relative displacement, such that elliptically polarized light, circularly polarized light, or linearly polarized light with an arbitrary polarization angle of 0°˜360° is generated when electron beams pass through the composite magnetic fields, and such that velocity directions of electrons are deviated from an axis direction of the undulator.

Abstract: A flywheel energy storage device includes the Halbach Motor/Generator with rolling biphasic coil control, continuously variable torque transfer via magnetic induction and a reluctance magnetic levitation system known as the Axial-Loading Magnetic Reluctance Device. Electric energy input turns the magnetically coupled rotors of the Halbach motor, and torque is transferred to a flywheel through a copper cylinder variably inserted between the Halbach magnet rotors. In idle mode, the energy is stored kinetically in the spinning flywheel, which is levitated by a permanent magnet bearing. Electric energy output is achieved by transferring torque from the flywheel through the copper cylinder to the rotors of the Halbach Generator by magnetic induction. Rolling biphasic motor control includes dividing Halbach motor coils into increments, then energizing groups of contiguous increments into virtual coils, which revolve in tandem with the magnet rotors so to achieve continuous and optimal torque.

Abstract: An apparatus, e.g. a cavity resonator, includes a floor and a cover. A conductive post is located between the floor and the cover and has a void oriented along a longitudinal axis of the post. A dielectric spacer is located between the cover and the post and a dielectric rod is located within the void. A resilient dielectric is located within the void between the dielectric spacer and the floor.

Abstract: A high performance superconducting undulator magnet is provided. The superconducting undulator magnet includes inset grooves in which magnetic poles are attached. The superconducting undulator magnet also includes clips for use in winding. The superconducting wire is wound such that the each revolution of the wire has a precise position within each of the grooves, the precise position being repeated in each groove. The superconducting undulator magnet provided will have a mechanical precision to preserve uniformity of the magnetic pole width and coil grooves. The undulator system provides uniformity of the undulator gap.

Abstract: Magnetic system possessing and producing polar and field properties comprising an application of organized ensemble of constituted constructions of magnetic apparatus as means of construction. The magnetic system as an application produces magnetic phenomena and interactions, such as the production of three different interactions and also their related respective three opposites, depending on the distance existing between the magnetic constructions. It is a fully systemized product that can be used as an experimental instrument for exploitation of new designing possibilities in magnetic constructions, containing also a process of operation.

Abstract: A method of axially aligning a charged particle beam implemented by a charged particle beam system equipped with an astigmatic correction lens including a first pair of coils and a second pair of coils. The method starts with obtaining first to sixth sets of image data while varying currents flowing through the first to fourth coils according to first to sixth sets of conditions. Then, the values of the currents through the first to fourth coils for correcting the position of the axis of the beam are calculated based on the first to sixth sets of image data.

Abstract: The present invention provides an inductively coupled, magnetically enhanced ion beam source, suitable to be used in conjunction with probe-forming optics to produce an ion beam without kinetic energy oscillations induced by the source.

Abstract: A periodic permanent magnet (PPM) klystron has beam transport structures and RF cavity structures, each of which has permanent magnets placed substantially equidistant from a beam tunnel formed about the central axis, and which are also outside the extent of a cooling chamber. The RF cavity sections also have permanent magnets which are placed substantially equidistant from the beam tunnel, but which include an RF cavity coupling to the beam tunnel for enhancement of RF carried by an electron beam in the beam tunnel.

Abstract: A switchable ion gun switchable between a cluster mode setting for producing an ion beam substantially comprising ionised gas clusters and an atomic mode setting for producing an ion beam substantially comprising ionised gas atoms, comprising: a source chamber having a first gas inlet; a gas expansion nozzle for producing gas clusters in the presence of gas atoms by expansion of a gas from the source chamber through the nozzle; an ionisation chamber for ionising the gas clusters and gas atoms; wherein the ionisation chamber has a second gas inlet for admitting gas directly into the ionisation chamber to form ionised gas atoms; and a variable mass selector for mass selecting the ionised gas clusters and ionised gas atoms to produce an ion beam variable between substantially comprising ionised gas clusters and substantially comprising ionised gas atoms.

Abstract: The present invention discloses a system for the administration of a plasma modified field (PMF) to a subject comprising: (a) a non thermal plasma (NTP) emitting source for emitting a plasma beam; (b) a plasma modified field coupling mechanism (PMFCM) comprising a plasma beam dish having at least one opening for the passage of said plasma beam; said plasma beam dish having a first surface and a second opposite surface; and (c) a controller for controlling said PMFCM. In a main aspect of the invention, said first surface of said plasma beam dish is mounted with: (i) at least one coupling element selected from the group consisting of: (1) at least one ferroelectric element for providing said field; (2) at least one ferromagnetic element for providing said field; (3) at least one piezoelectric element for providing said field; and (4) at least one piezomagnetic element for providing said field; and (ii) at least one reflecting element.

Abstract: Various embodiments of a vacuum electronic device, a hybrid magnet for a vacuum electronic device and methods of making a hybrid magnet for a vacuum electronic device are disclosed herein. In one embodiment, a hybrid magnet for a vacuum electronic device includes a first magnet, a second magnet positioned in spaced-apart relation with the first magnet and defining a gap between the first magnet and the second magnet, and a non-magnetic spacer positioned in a portion of the gap between the first magnet and second magnet and connected to the first magnet and the second magnet.

Abstract: Electron beam-confining electromagnets of an electron beam generator are aligned with an electron beam axis, each of the electromagnets being folded to define a main section and a pair of angled wing sections disposed at respective angles relative to said main section, and a conductor wound around the edge.

Abstract: A method of axially aligning a charged particle beam implemented by a charged particle beam system equipped with an astigmatic correction lens including a first pair of coils and a second pair of coils. The method starts with obtaining first to sixth sets of image data while varying currents flowing through the first to fourth coils according to first to sixth sets of conditions. Then, the values of the currents through the first to fourth coils for correcting the position of the axis of the beam are calculated based on the first to sixth sets of image data.

Abstract: A variety of systems, apparatus and methods for deflecting a particle beam are described. An apparatus comprises at least six electromagnetic portions disposed on a plane. Each of the at least six electromagnetic portions is aligned with a radius emanating from an axis normal to the plane and is distanced from the axis to form a volume about the axis. At least six coils are configured for affecting a dipole magnetic field in the volume in response to electrical currents applied to physically opposing coils where a particle beam entering the volume is deflected. Each of the at least six coils is disposed about a one of the at least six electromagnetic portions. A yoke structure is configured for returning a generated magnetic flux.

Abstract: An electron tube includes a microwave structure, an electron gun having a cathode-wehnelt assembly, with axis for providing a linear electron beam along the same axis in a circular cylindrical passage with axis of the microwave structure, the cathode comprising a centre of rotation of the beam on the said axis of the cathode. The electron gun and the microwave structure each comprise portions of spherical surfaces in contact inscribed on one and the same sphere of radius centred on the centre of the cathode so as to form a swivel for angular adjustment of the axis of the cathode and to make the axis of the electron beam coincide with the axis of the circular cylindrical passage of the microwave structure. Applications include microwave electron tubes such as travelling wave tubes and klystrons.

Abstract: A planar-helical undulator for emitting 360° electrically variable photo radiation, including a first coil and a second coil disposed relative to an undulator axis, an axis of the first coil and an axis of the second coil and the undulator axis being parallel to each other, and the undulator axis forming a portion of a synchrotron beam axis. Further, each of the first and second coils includes a helical section and a planar section. The windings of each respective section are connected in series, so that the planar section generates, when energized, a first magnetic field, and so that the helical section generates, when energized, a second magnetic field. Each planar section is disposed around the corresponding helical section, and at least one of the helical section and the planar section of at least one of the coils includes variable windings changing symmetrically over a length of the respective section towards a middle of the respective section.

Abstract: A terahertz sheet beam klystron (TSBK) includes an electron gun configured to generate a sheet electron beam and a drift tube through which the sheet beam is propagated. The drift tube is provided with multiple resonant cavities and includes a drift tube circuit including an input RF circuit through which an input RF signal is introduced and an output RF circuit through which an output RF signal is extracted, a collector, and a vacuum envelope. The output RF circuit is configured such that Qe (extraction Q) of the drift tube circuit is comparable to Q0 (unloaded Q) of the drift tube circuit, thereby improving the efficiency of the drift tube circuit.

Abstract: A collector sweeping method for controlling an electron beam in a beam collector, in particular of a magnetic gyrotron device, comprises the steps of subjecting the electron beam to a transversal sweeping field having a field component perpendicular to a longitudinal direction (z) of the beam collector and providing a tilted, rotating intersection area of the electron beam in the beam collector, and varying at least one of a longitudinal position and a tilting angle of the intersection area by a modulation of the transversal sweeping field. Furthermore, a collector sweeping apparatus and a microwave generator are described.

Abstract: A multi-column electron beam exposure apparatus includes: multiple column cells; an electron beam converging unit in which two annular permanent magnets and electromagnetic coils are surrounded by a ferromagnetic frame, each of the two annular permanent magnets being magnetized in an optical axis direction and being symmetrical about the optical axis, the electromagnetic coils disposed near the annular permanent magnets and used to adjust magnetic fields of the annular permanent magnets; and a substrate provided with circular apertures through which electron beams used in the column cells pass, respectively, the substrate having the electron beam converging unit disposed in a side portion of each of the circular apertures. The two annular permanent magnets may be disposed one above the other in the optical axis direction with same polarities facing each other, and the electromagnetic coils may be provided inside or outside the annular permanent magnets in their radial direction.

Abstract: A klystron has a hollow beam electron gun that has a circular planar electron emitting surface. A hollow electron beam is directed from the electron gun through a plurality of drift tubes, resonant chambers and magnetic fields to a collector. The hollow electron beam does not experience significant radial movement and can operate at a lower beam voltage which reduces the required length of the RF interaction circuit and lowers the risks of RF arcing.

Abstract: The present invention provides an enhanced THz electromagnetic source structure achieving a very high aspect ratio of 500 to 1 of electron beam width to electron beam thickness of the electron beam moving in the direction across the grating structure while maintaining its cross-section. The structure comprises a magnetic circuit providing a unique low magnetic field slot placed in a steel core for the placement of an electron gun, thus allowing the electron beam to be focused without the interaction of a magnetic field while still supporting a high magnetic field in the grating region. Additionally, the structure comprises an electrostatic shield preventing potential difference between the anode voltage and the grounded steel core from affecting the focusing of the electron beam.

Abstract: A magnet configuration for a power microwave tube with a resonant cavity comprises a permanent magnet (110) with an axis-aligned through-bore (135) of sufficient size to contain the resonant cavity. The permanent magnet has an inner chamber (140) that is centered on the axis (130) with opposite magnet poles aligned along the axis. The magnet configuration further comprises an electromagnet coil (120) fitting in the chamber and encircling the axis such that the coil produces a magnetic field that reinforces the magnetic field from the permanent magnet. An optional protrusion (125) spanning the through-bore narrows an air gap between the poles. The method provides a magnetic field in a power microwave generator by combining a permanent magnet with an electromagnet in accordance with the magnet configuration and energizes the electromagnetic coil, which may be by pulsing the coil current.

Abstract: An output power adjusting mechanisms for adjusting output power is provided on a wave guide of a high frequency output section coupled to an output cavity. The output power adjusting mechanisms is located at a position apart away from the output cavity by a distance of ? wavelength or [(? wavelength)×odd number]. The output power adjusting mechanism includes a reflection adjusting part which is provided in the tube wall of the wave guide so as to be displaceable in the inward and outward directions of the output tube. The output power is adjusted by displacing the reflection adjusting part.

Abstract: A permanent magnet focusing system includes an electron gun that provides an electron ribbon beam having an elliptical shape. A plurality of permanent magnets provide transport for the electron ribbon beam. The permanent magnets produce a non-axisymmetric periodic permanent magnet (PPM) focusing field to allow the electron ribbon beam to be transported in the permanent magnet focusing system.

Abstract: An electron beam amplification device provides trajectory modulation of an electron beam, and includes an electron gun, a modulator, an interceptor, an output circuit, and a collector. The electron gun produces an electron beam. The modulator receives an RF input signal and provides a corresponding electromagnetic field region that alters trajectory of the electron beam in correspondence with the RF input signal. The interceptor has at least one aperture oriented such that the electron beam transmits through the aperture when the electron beam altered by the modulator follows a particular transmission path and impacts upon the interceptor when the electron beam trajectory altered by the modulator follows a path other than the particular transmission path. The output circuit is arranged so that the electron beam transmitted through the interceptor aperture passes therethrough and produces an RF output signal. The collector recovers remaining energy of the electron beam after passing through the output circuit.

Abstract: An electron beam tube device has a magnetic frame with the top part being pivotable so as to pivot from a closed position in which the top part, including an electromagnetic coil covers the electron beam tube to an open position in which the electron beam tube is uncovered. This allows electron beam tubes with either large parts or integral parts such as output feeders to be removed from the magnetic frame without complete removal of the top plate.

Abstract: A novel method of gating electron emission from field-emitter cathodes for radio frequency (RF) electrode guns and a novel cathode that provides a focused electron beam without the need for magnetic fields or a curved cathode surface are provided. The phase and strength of a predefined harmonic field, such as the 3rd harmonic field, are adjusted relative to a fundamental field to cause a field emission cathode to emit electrons at predefined times for the generation of high-brightness electron beams. The emission time is gated responsive to the combined harmonic and fundamental fields and the response of the FE cathode to the combined fields. A planar focusing cathode includes a selected dielectric material, such as a ceramic material, to provide an electron beam emission surface. Metal surfaces are provided both radially around and behind the dielectric material to shape the electric fields that accelerate and guide the beam from the cathode surface.

Abstract: An amplifying device comprises an electron gun emitting an electron beam, a collector spaced from the electron gun, the collector oriented to collect electrons of the electron beam emitted from the electron gun, and an interaction structure interposed between the electron gun and the collector. The interaction structure defines an electromagnetic path along which an applied electromagnetic signal interacts with the electron beam. The interaction structure further comprises a plurality of polepieces and a plurality of magnets, the polepieces each having an aligned opening to collectively provide an electron beam tunnel having an axis extending between the electron gun and the collector to define an electron beam path for the electron beam. The polepieces provide a magnetic flux path to the electron beam tunnel from the magnets. More particularly, the interaction structure further includes plural cavities defined therein interconnected to provide a coupled cavity circuit.

Abstract: An output power adjusting mechanisms for adjusting output power is provided on a wave guide of a high frequency output section coupled to an output cavity. The output power adjusting mechanisms is located at a position apart away from the output cavity by a distance of ? wavelength or [(? wavelength)×odd number]. The output power adjusting mechanism includes a reflection adjusting part which is provided in the tube wall of the wave guide so as to be displaceable in the inward and outward directions of the output tube. The output power is adjusted by displacing the reflection adjusting part.

Abstract: An undulator includes a periodic arrangement of magnets to produce a periodic spatial magnetic field distribution in a magnetic gap defined by the magnets. The undulator further includes a temperature-compensating material selectively arranged to compensate for a temperature-dependent change in the magnetic field of the undulator. The change may be in the strength of the magnetic field, or in the position of the magnetic field centerline. According to one aspect of the invention, the temperature-compensating material is movably arranged, so as to fine tune its compensation effect after it is initially arranged. Alternatively or additionally, the amount of temperature-compensating material may be adjusted to fine tune its compensation effect after it is initially arranged.

Abstract: A linear electron beam tube comprises an electron gun having a cathode and a grid, and an anode arranged in a first portion of a drift tube. The drift tube is within a vacuum envelope and has first and second portions separated by a gap at which point an electron beam, density modulated with an input RF signal is inductively coupled to an output cavity. The vacuum envelope is partially defined by a cylindrical ceramic wall and a pair of ferromagnetic pole pieces at its ends that form a DC magnetic circuit. The pole pieces extend radially beyond the vacuum envelope. At least those parts of the surface of the pole pieces that are in the RF path are coated with a layer of relatively low RF loss material such as copper. A balance ring separates the ceramic from the pole pieces.

Abstract: In an undulator for the generation of synchrotron radiation from a particle beam introduced into the undulator, two partial undulators are provided each comprising a conductor of superconductive material which, when a current is conducted therethrough, generates an undulator field that extends perpendicularly to the current flow, and the superconductive conductors are arranged in the individual partial undulators such that the undulator fields generated are not parallel, whereby, by controlling the energization of the two partial undulators, the polarization direction of the synchrotron radiation can be adjusted without mechanical movements.

Abstract: A multibeam, electrostatically focused klystron includes a plurality of conductive members, ones of which are recessed to provide input and output sections of microwave cavities, wherein focusing voltage is applied between those sections. The conductive members are either spaced along the path of multiple beams, or stacked in insulated relation, in either case being supported by glass rods within a glass envelope.

Abstract: An inductive output tube (IOT) provides improved efficiency and larger bandwidth. In one embodiment, an IOT is provided with an electron gun that generates an electron beam, a tube body, a collector for collecting the electron beam, and an extended-interaction output circuit. The electron beam travels through the tube body and the extended-interaction output circuit. The extended-interaction output circuit is located within the tube body. The extended-interaction output circuit comprises a short-circuited resonant structure. The extended-interaction output circuit is used for reducing undesired components of a radio frequency (RF) wave, increasing desired components of the RF wave, and slowing down the propagation of the RF wave. (That is the circuit increases the integral of the electric field along the path of the beam electrons while decreasing the stored energy associated with those fields.) The extended-interaction output circuit also provides the IOT with larger bandwidth operation.

Abstract: A novel method of gating electron emission from field-emitter cathodes for radio frequency (RF) electrode guns and a novel cathode that provides a focused electron beam without the need for magnetic fields or a curved cathode surface are provided. The phase and strength of a predefined harmonic field, such as the 3rd harmonic field, are adjusted relative to a fundamental field to cause a field emission cathode to emit electrons at predefined times for the generation of high-brightness electron beams. The emission time is gated responsive to the combined harmonic and fundamental fields and the response of the FE cathode to the combined fields. A planar focusing cathode includes a selected dielectric material, such as a ceramic material, to provide an electron beam emission surface. Metal surfaces are provided both radially around and behind the dielectric material to shape the electric fields that accelerate and guide the beam from the cathode surface.

Abstract: The invention relates to amplifying electron tubes operating at microwave frequencies. The electron tube comprises: a pump-out tube that allows the vacuum inside the electron tube to be created; an electron gun that emits an electron beam inside the electron tube; a collector that directly collects a first portion of the electron beam. The pump-out tube directly repels a second portion of the electron beam in the direction of the collector.

Abstract: An exemplary system and method for providing a multi-layer klystron-type electron beam device for the generation and amplification of millimeter-wave electromagnetic radiation is disclosed as comprising inter alia: a cathode layer (130); a collector layer (100); an extraction layer (120); a control layer (140); an input cavity (150); an output cavity (170); several ceramic spacer layers (103, 105, 107) dispose intermediately between the cathode (130) and the collector (100); and optionally, several magnetic ceramic layers (160, 165) for beam forming and focusing. After the klystron's layers are assembled, the device may be fired to form a substantially monolithic structure.

Abstract: A klystron tube for amplifying signals at microwave radio frequencies utilizes an electron source for emitting electrons through a field focused by a high energy magnet in the RF section of the tube. After the electrons have passed through the active area of the tube, the electrons strike the collector which, in this case, is a multistage depressed collector. The multistages of the depressed collector are connected to high energy voltage sources of different potentials. The klystron tube with the multistage depressed collector is uniquely used here for the first time in a ground based satellite or terrestrial communications system.

Abstract: An RF device comprising a plurality of drift tubes, each drift tube having a plurality of gaps defining resonant cavities, is immersed in an axial magnetic field. RF energy is introduced at an input RF port at one of these resonant cavities and collected at an output RF port at a different RF cavity. A plurality of electron beams passes through these drift tubes, and each electron beam has an individual magnetic shaping applied which enables confined beam transport through the drift tubes.

Abstract: An improved Klystron device is disclosed which has opposed electrostatic (ES) magnetic field generating members which are uniformly spaced along a longitudinal axis to form an electron beam chamber. The ES magnetic field generating members produce a magnetic flux which confines an electron beam passing through the chamber when an alternating current (AC) is imposed upon the magnetic field generating members. An additional improvement includes a chamber formed from a single sheet of electron conductive metal having a ladder-like structure symmetrical about a longitudinal hinge which permits the structure to be folded about the hinge to form a suitable electron beam chamber.

Abstract: An exemplary system and method for providing a multi-layer klystron-type electron beam device for the generation and amplification of millimeter-wave electromagnetic radiation is disclosed as comprising inter alia: a cathode layer (130); a collector layer (100); an extraction layer (120); a control layer (140); an input cavity (150); an output cavity (170); several ceramic spacer layers(103, 105, 107) dispose intermediately between the cathode (130) and the collector (100); and optionally, several magnetic ceramic layers (160, 165) for beam forming and focusing. After the klystron's layers are assembled, the device may be fired to form a substantially monolithic structure.

Abstract: A klystron tube for amplifying signals at microwave radio frequencies utilizes an electron source for emitting electrons through a field focused by a high energy magnet in the RF section of the tube. After the electrons have passed through the active area of the tube, the electrons strike the collector which, in this case, is a multistage depressed collector. The multiple stages of the depressed collector are connected to high energy voltage sources of different potentials. The magnet used for focusing the electron beam is closed (no open pole pieces) at the multistage depressed collector so that no magnetic flux reversals are present to affect the beam dispersal, due to electrostatic space charge forces, onto the multistage depressed collector.

Abstract: The invention is a color cathode-ray tube having a rectangular front face (1) connected to a funnel shaped rear part (2), a neck (2a) connected to the rear part and having an electron gun (6) therein, the gun is used to generate beams intended to scan the front face under the influence of a deflection device (10) placed on the neck of the tube. The deflection device comprising correction magnets (20) placed on the periphery of the device in locations closest to the front face and a magnetic screen (30) within the tube having an opening (31) for passage of the electron beams, wherein the opening has notches (34) in its periphery. The notches are arranged so as to face at least one pair of correction magnets (20).

Abstract: An electron gun that generates multiple electron bunches and the application of this gun to produce rf energy. The electron gun includes an rf input cavity having a first side with multiple emitting surfaces and a second side with multiple transmitting and emitting sections. The gun also includes a mechanism for producing a rotating and oscillating force which encompasses the multiple emitting surfaces and the multiple sections so electrons are directed between the multiple emitting surfaces and the multiple sections to contact the multiple emitting surfaces and generate additional electrons and to contact the multiple sections to generate additional electrons or escape the cavity through the multiple sections. A method for producing multiple electron bunches.