99results about "Discharge tube solid thermionic cathodes" patented technology

The embodiment of the utility model provides a cathode assembly and an electron emission device. The cathode assembly comprises a cathode emitter, the first end of the cathode emitter is used for emitting electrons outwards, and the material of the cathode emitter at least comprises boride; the first heating part is used for irradiating the cathode emitter with laser so as to heat the cathode emitter; the second heating part is connected to the second end of the cathode emitter, and the second heating part heats the cathode emitter by generating joule heat; and the second heating component is used for heating the cathode emitter together with the first heating component after the first heating component heats the cathode emitter to a first temperature threshold value.

The invention relates to an electron extraction method and system for a low-energy electron source. The method comprises the following steps: providing at least one cathode, at least one heating power supply and at least one control electrode; in a first time period, the heating power supply provides heating current for the cathode, so that the temperature of the cathode is increased to be higher than an electron emission threshold value, meanwhile, the potential difference between the control electrode and the cathode is controlled to be a suppression value, and electrons generated by the cathode are prevented from reaching a preset target spot; and in the second time period, the current is stopped from being supplied to the cathode, and meanwhile, the potential difference between the control electrode and the cathode is controlled to reach a guide value, so that electrons emitted by the cathode through waste heat reach the preset target spot and interact with target particles. Cathode heating is controlled in an intermittent energization mode, and accurate extraction of the low-energy scattered electron beam is achieved.

[Problem] To provide novel technology. [Solution] One aspect of the present invention provides a thermionic cathode. The thermionic cathode includes an electron source and a plurality of grids. The electron source is configured to emit electrons when heated. The plurality of grids have through-holes that allow electrons emitted from the electron source to pass in a predetermined direction. At least one of the grids is configured to reduce the movement speed of the electrons.

The electron source is provided with: an electron emission unit containing an alloy of iridium and a rare earth element; a support part made of metal; and a joining part that joins the electron emission part and the support part. The bonding portion has a coating layer containing iridium and the metal in the support portion, and the coating layer contains iridium and the metal in the support portion.

To provide an electron source comprising an insulating base, a pair of conductive terminals, an insulating support member, a drift separation member, an emitter-cathode, and one or more heating elements.SOLUTION: Conductive terminals are exposed from a first surface of an insulating base. An insulating support member extends from the first surface of the insulating base. A drift isolation member is disposed at an end of the insulating support member remote from the insulating base. An emitter-cathode is coupled to the drift isolation member. One or more heating elements are coupled to the conductive terminals and the drift isolation member. Combination of the drift isolation member with the insulating support member can prevent stress-induced drift from impacting a position of the emitter-cathode, thereby improving mechanical stability of the electron source.SELECTED DRAWING: Figure 1A

This emitter comprises: an insulator; a pair of conductive terminals attached to the insulator and spaced apart from each other; a heater that is arranged between the tip sections of the pair of insulator terminals and emits heat as a result of being energized; an electron source formed from a first material that is heated by the heater and releases electrons; a Wehnelt electrode that has an inner surface forming an interior space together with the surface of the insulator, and that serves to apply bias voltage between said Wehnelt electrode and the electron source; and a shielding member covering part of the surface of the insulator within the interior space.

A cathode device with an electrical contact junction that operates cooler and has more stable electrical resistance than prior art Provision of. The cathode device includes an emitter tip (16) for generating electrons. It includes an elongated heater (14) having a proximal end and a distal end. The emitter tip can be located at the distal end of the heater. Two spaced-apart legs (15a, 15b) extend away from the heater's distal end and terminate at the proximal end, forming an elongated slot therebetween. Two electrical contacts (20) compressively engage opposite outer surfaces of the two legs at the heater's proximal end to mechanically secure and electrically connect the two legs to their respective electrical contacts at a junction located away from the emitter tip to maintain a lower junction temperature.

A cathode heater assembly for use in a vacuum electronic device comprises a refractive cup having a bottom portion and side walls forming a container: a cathode secured in the container of the refractive cup; and a heater wire coupled to the refractive cup. The cathode heater assembly may be manufactured by providing a refractive cup having a bottom portion and side walls forming a container; inserting a cathode pellet in the container of the refractive cup; impregnating the cathode pellet with electron emissive materials while the cathode pellet is in the container of the refractive cup; and attaching a heater wire to the refractive cup.

According to the cathode structure of the ionizer, a large arc structure formed by winding one metal hot wire in the prior art is changed into a small arc structure formed by winding two metal hot wires, the pins are arranged at the two ends of each metal hot wire, and the metal hot wires are fixed to the sheet electrodes through the pins, so that the cathode structure of the ionizer is formed. According to the metal hot wire, the first end of the sheet-shaped electrode is provided with a pin positioning groove or an arc-shaped surface and a limiting step, so that the original multi-point welding between the linear pin and the sheet-shaped electrode is changed into straight welding, the angular tensile stress during welding is reduced, the metal hot wire is not prone to deformation in the assembling process, and the concentricity of the metal hot wire and other electrodes is kept; the stability of a small arc structure formed after welding is improved, a welding area of the metal hot wire and the sheet electrode is far away from a high-temperature area of the metal hot wire by arranging the linear pins, an effective electron emission area is enlarged, and heat loss generated by heat conduction is reduced. The efficiency of the metal heating wire is remarkably improved, the metal heating wire is not prone to fusing failure, and the service life is prolonged.

An electron source according to the present disclosure includes a columnar portion made of a first material having an electron emission characteristic; and a tubular portion that is disposed to surround the columnar portion and made of a second material having a higher work function than the first material, wherein a hole that extends in a direction from one end face toward the other end face and has a substantially circular cross-sectional shape is formed in the tubular portion, and the columnar portion has a substantially triangular or substantially quadrangular cross-sectional shape and is fixed to the tubular portion in an abutting engagement with an inner surface of the hole.

A method for manufacturing an electron source according to the present disclosure includes steps of: (A) preparing a first member provided with a columnar portion made of a first material having an electron emission characteristic, (B) preparing a second member which has a higher work function and a lower strength than the first material, and in which a hole is formed extending in a direction from one end surface toward the other end surface, and (C) pushing the columnar portion into the hole in the second member, wherein the first member has a cross-sectional shape that is dissimilar to the cross-sectional shape of the hole; and in the step (C), by pressing the columnar portion into the hole, a portion of a side surface of the columnar portion scrapes the inner surface of the hole and bites into the second member, thereby fixing the columnar portion to the second member.

An ion source for forming a plasma includes a cathode having a cavity and a cathode surface defining a cathode step. A filament is disposed within the cavity, and a cathode shield has a cathode shield surface at least partially surrounding the cathode surface. A cathode gap is defined between the cathode surface and the cathode shield surface, and the cathode gap defines a tortuous path for restricting movement of the plasma through the gap. The cathode surface may have a stepped cylindrical surface defined by a first cathode diameter and a second cathode diameter. The first cathode diameter and the second cathode diameter are different from each other to define the cathode step. The stepped cylindrical surface may be an outer surface or an inner surface. The first cathode diameter and the second cathode diameter may be concentric or axially offset.

The invention belongs to the technical field of electron flow emitting devices, and particularly relates to a device for enhancing electron emission guidance quality, which comprises a base, a guide piece column and at least one lamp filament, each pair of conductive columns penetrate through the base and are electrically connected with a power supply, and the lamp filament is electrically connected with the conductive columns. The conductive column is fixedly installed on the base, the lamp filament is installed on the base, the insulating parts are arranged at the two ends of the connecting position of the conductive column and the base respectively and wrap the conductive column, and the guiding part is fixedly installed on the base and located behind the lamp filament so that the situation that electrons emitted by the lamp filament thermally flow to a non-working area to be dissipated can be reduced. The density of the electron flow is controlled, the use of multiple working areas is met, and the dissipation direction of the electron flow can be controlled through the guide piece.

Various methods and systems are provided for an emitter assembly for a cathode of an X-ray tube. In one example, an emitter assembly comprises a first end of a substantially flat emitter supported by two rods extending from a two-rod insulator assembly, and a second end of the substantially flat emitter supported by a compliant, single rod insulator assembly.

To provide an electron source which can have sufficient electron emission characteristics even after a certain time elapses from start of emission of electrons, and to provide a manufacturing method of the electron source.SOLUTION: An electron source 100 includes: an electron emission member 10 containing iridium and lanthanoid; a conductive support member 20 which supports the electron emission member 10; and a conductive member 30 disposed between the electron emission member 10 and the support member 20 and in contact with both. In a manufacturing method of the electron source 100, the electron emission member 10 and the support member 20 are joined through the conductive member 30.SELECTED DRAWING: Figure 2

To provide an indirect heated cathode capable of shortening the time up to a start of radiation of thermoelectrons, and a method of manufacturing the indirect heated cathode in which a heat absorption layer which has a uniform thickness can be easily manufactured.SOLUTION: An indirect heated cathode 10 comprises a cathode sleeve 1, a heater 2 arranged at a hollow part of the cathode sleeve 1, a black heat absorption layer 4 covering a hollow part inner surface of the cathode sleeve 1, and a cathode base body 3 carrying an electron emission substance arranged at the cathode sleeve 1. The black heat absorption layer 4 consists of a particulate substance including tungsten and aluminum oxide. The black heat absorption layer 4 is formed by arranging rod-like alumina ceramics, and a first tungsten heater and a second tungsten heater in the hollow part of the cathode sleeve 1 and heating it in a vacuum atmosphere.SELECTED DRAWING: Figure 1

An emitter (1) having: an electron source tip (10); a first filament (50) connected to a first position (10a) on the side surface of the electron source tip (10); a second filament (60) connected to a second position (10b) on the side surface of the electron source tip (10); two upper positive terminals (20a, b) connected to first side surfaces (50a, b) at two locations of the first filament (50), respectively; two upper negative terminals (20c, d) connected to second side surfaces (60a, b) at two locations of the second filament (60), respectively; one lower positive terminal (30a) electrically connected to the two upper positive terminals (20a, b); one lower negative terminal (30b) electrically connected to the two upper negative terminals (20c, d); and an insulator (40) carrying the upper positive terminals (20a, b), the upper negative terminals (20c, d), the lower positive terminal (30a), and the lower negative terminal (30b), the first position (10a) and the second position (10b) being different positions, the first side surfaces (50a, b) of the first filament (50) being connected to the side surfaces of the upper positive terminals (20a, b), respectively, and the second side surfaces (50a, b) being connected to the side surfaces of the lower positive terminals (30a, b). The second side surfaces (60a, b) of the second filament (60) are connected to the side surfaces of the upper negative terminals (20c, d), respectively.

The present invention relates to an annular cathode for a vacuum tube, which comprises: - a cylindrical central support (7) whose axis is the axis of the cathode; - an outer peripheral electron emitter (6) with an annular cross-section extending above the outer periphery of the cathode, the axis of the electron emitter (6) being the axis of the cathode; and, - a folded skirt (4) which is fixed to the central support (7) at its inner end and is fixed to a plurality of lugs (5) at its outer end; - each lug (5) is arranged in series with the folded skirt (4) and is fixed to the folded skirt (4) and to the inner surface of the electron emitter (6).

In one embodiment, a system includes a cathode and a thermionic emitter installed at least partially within the cathode tube of the cathode. The thermionic emitter is in a shape of a hollow cylinder. The hollow cylinder includes an outer surface and an unsmooth inner surface. The outer surface is configured to contact an inner surface of the cathode tube. The unsmooth inner surface includes a plurality of structures that provide an increase in surface area over a smooth surface.

An electron beam generating source includes an electron emitting portion extending in a desired axis and emitting electrons, a movable portion connected to one end of the electron emitting portion, a support portion supporting the movable portion in a manner that the movable portion is movable along the axis, and a tension maintaining portion maintaining tension of the electron emitting portion by applying a pressing force or a stretching force to the movable portion. The movable portion and the tension maintaining portion are disposed on the axis, respectively.

The invention provides a heater-free hollow cathode with a built-in tungsten filament electrode, and belongs to the technical field of spaceflight related equipment manufacturing. An emitter is arranged on the upper portion of the inner side wall of a cathode tube and tightly attached to the inner side wall of the cathode tube, the outlet end of the top of the cathode tube is connected with a throttling top in a sealed mode, a first flow channel of the throttling top is communicated with the cathode tube and an emitter cavity, the cathode tube is coaxially sleeved with a touch holding electrode, and the bottom end of the cathode tube is fixedly connected with the top end face of a ceramic base. The built-in tungsten filament electrode is fixed in the second flow channel of the ceramic base, the top end of the built-in tungsten filament electrode is arranged in the cavity of the emitter and does not make contact with the surface of the emitter, the first through hole of the ceramic base is communicated with the third flow channel and sealed, and a ceramic insulating layer is arranged on the bottom end face of the touch holding electrode. And the two conductive columns pass through the two through holes II of the ceramic insulating layer and are fixedly connected with the contact holding electrode. In the cathode starting process, an external heating structure of a traditional cathode can be optimized by means of the heat emission effect of a tungsten filament in the cathode, and therefore miniaturization of the cathode is achieved.

A filament assembly 10 for an x-ray tube 20 can include a planar filament 11 electrically-coupled between and substantially-encircled by a pair of collector plates C1 and C2. The pair of collector plates C1 and C2 can support the planar filament 11 so that it does not twist or warp and align the filament assembly 10 within a cathode cup 33. The pair of collector plates C1 and C2 can block electrons emitted from a back side of the filament. Without the collector plates C1 and C2, back side electrons can change direction by about 180°, hit the target, and distort a target electron spot. Each collector plate C1 or C2 can include holes H1 and H2. These holes H1 and H2 can aid in alignment of the collector plates C1 and C2 with electrodes 31 and electrode 32, can allow welding at a lower temperature, and can facilitate weld inspection.

A monolithic graphite heater for heating a thermionic electron cathode includes first and second electrically conductive arms, each one of the first and second electrically conductive arms having an electrode mount at a proximal end, a thermal apex at a distal end, and a transitional region between the electrode mount and the thermal apex; a cathode mount electrically and mechanically coupling each thermal apex to form a maximum Joule-heating region at or adjacent the cathode mount and decreasing Joule heating along each transitional region; and a press-fit aperture formed in the cathode mount, the press-fit aperture sized to receive at least a portion of the thermionic electron cathode for facilitating thermionic emission produced therefrom in response to operative heat power generation provided by the maximum Joule-heating region.

To provide an emitter which can effectively suppress generation of excess electrons and can improve structural stability, while suppressing variation in electron emission characteristics.SOLUTION: An emitter comprises: an electron source 2; and a heater 3 for heating the electron source 2. The electron source 2 has: an electron emission member 10 which is made of a first material; and a surrounding member 20 which is made of a second material having a work function greater than that of the first material. The electron emission member 10 has: a first portion 11; and a second portion 12 which is made integral with the first portion 11. The surrounding member 20 is fixed to the electron emission member 10, and it surrounds the first portion 11 when viewed from a direction A. The minimum thickness of the surrounding member 20 is 20 μm or more. The heater 3 is in contact with the second portion 12.SELECTED DRAWING: Figure 2

The application discloses a barium tungsten lanthanum hexaboride composite hollow cathode, which comprises a cathode tube, a gas inlet is arranged at a first end of the cathode tube, a cathode top is arranged at a second end of the cathode tube, and a cathode top through hole is arranged in the cathode top; a touch electrode is arranged outside the cathode tube, an end of the touch electrode is provided with a touch electrode top, a touch electrode through hole is arranged in the touch electrode top, and the touch electrode is coaxial with the cathode tube; an emitter comprises a first emitter and a second emitter, the first emitter and the second emitter are sequentially arranged on an inner wall of the second end of the cathode tube in a direction from the gas inlet to the cathode top; a heater is arranged around an outer wall of the cathode tube; wherein the first emitter is a barium tungsten emitter, the second emitter is a lanthanum hexaboride emitter, and the lanthanum hexaboride emitter is heated by heat generated by self-sustaining work of the barium tungsten emitter, so that the starting power consumption is greatly reduced.

The invention relates to the field of electronic gun power supplies, and discloses an electronic gun filament power supply isolation device and electronic gun equipment, and the electronic gun filament power supply isolation device comprises a driving circuit which is used for outputting a driving signal when receiving a control signal; the first motor is connected with the driving circuit, and the first motor is used for working when receiving the driving signal; the insulation transmission structure is connected with the first motor; the second motor is connected with the insulation transmission structure and is also used for connecting an electron gun filament; the first motor drives the insulation transmission structure to rotate when working so as to drive the second motor to generate alternating current and output the alternating current to the electron gun filament. Through the first motor, the insulation transmission structure and the second motor, conversion from electric energy to mechanical energy and then to the electric energy is achieved, the structural design of a power circuit is simplified while electrical isolation and insulation are achieved, and the energy transmission efficiency is improved.

A device (1) for generating an electron beam (4), the device comprising: an elongated wire-shaped hot cathode from which the electron beam (4) is emitted, the electron beam having an elongated, linear cross-section perpendicular to its propagation direction due to the elongated shape of the hot cathode; a cathode electrode (2) and an anode electrode (3), between which a voltage for accelerating electrons escaping from the hot cathode is applied; and a deflection unit capable of deflecting the electron beam (4) penetrating an opening of the anode electrode (3), wherein during operation of the device, the cross-section of the electron beam (4) is changed by the deflection unit so that the extension in the longitudinal direction of the line is reduced and the extension in the transverse direction of the line is increased, in particular, the extension in the longitudinal direction of the line is approximately the same as the extension in the transverse direction of the line.

PURPOSE: To provide a cathode mechanism with which it is possible to extend the life of a cathode with which a desired luminance distribution is obtained.CONSTITUTION: The cathode mechanism of an electron gun comprises: a crystal 10 having an upper part of a columnar or truncated cone shape or a combination of these having a first face that emits thermoelectrons upon heating, and a lower part having a second face which is substantially parallel to the first face and larger in diameter size than the maximum diameter size of the upper part and being constructed integrally with the upper part; a holding part 12 which is formed in cylindrical form having a plurality of different inner diameters from the upper face side, including a first diameter size and a second diameter size larger than the first diameter size, and which holds the crystal in such a state that the first face of the crystal protrudes from the upper face and is in contact with the second face of the crystal in the cylinder; and a hold-down part 13 for holding down the crystal on the lower reverse side of the crystal so as not to come off from the holding part.SELECTED DRAWING: Figure 3