54results about How to "Large emission current" patented technology

The invention provides a field emission plane light source which comprises the components of: an anode, a focusing electrode, a gate electrode, a cathode and an isolator. The anode, the focusing electrode, the gate electrode, the cathode and the isolator form a vacuum sealed chamber. The anode comprises an anode substrate, an anode conducting layer and a light emitting layer successively. The isolator comprises an isolator body and a side wall supporting member. The isolator body is provided with a funnel-shaped through hole. The large opening end of the isolator body is connected with the light emitting layer, and the small opening end is connected with the focusing electrode through the side wall supporting member. The focusing electrode is provided with a focusing through hole which can focus electrons. The gate electrode is provided with a gate electrode through hole which allows passing-through of electrons that are transmitted by the cathode. The gate electrode is sandwiched between the focusing electrode and the cathode through the side wall supporting member. The cathode comprises a circular sheet-shaped cathode emitter, a cathode conducting layer and a cathode substrate successively. The upper surface of the cathode conducting layer is provided with a plurality of cathode emitters. The invention further provides a preparing method for the field emission plane light source.

The invention discloses a single-zone plate type high-temperature electrostatic dust collector and belongs to the technical field of environmental-protection dust collecting equipment. The equipment mainly comprises positive plates, a negative plate, emitter electrodes, a high-temperature power supply, wherein two stainless steel plates are grounded and parallelly arranged to serve as positive plates; a stainless steel plate which has the same shape and size as the positive plates is connected with the negative pole of a high-temperature power supply to serve as the negative plate; the negative plate is suspended in the middle of the two positive plates and parallel to the positive plates; and all disc-like emitter electrodes are embedded on the two sides of the negative plate. In the invention, a single-zone plate type structure is adopted, so the structure of the equipment is compact and the electrical field is uniform, and the stability and reliability of the high temperature operation of the equipment are improved; and the emitter electrode is made of cerium oxide-doped barium-tungsten hot electron emitting material, which contributes to improving dust collection efficiency and prolonging the service life of the equipment.

The invention discloses an on-chip micro electron source and a manufacturing method thereof. The on-chip micro electron source is provided with a heat conducting layer, and at least one electrode in the same pair of electrodes is connected with the heat conducting layer via a through hole of an insulating layer, so that heat generated by the on-chip micro electron source can be dissipated throughthe electrode and the heat conducting layer, and thus the heat dissipation ability of the on-chip electron source is significantly improved. Therefore, the on-chip micro electron source can integratemultiple single electron sources on the same substrate so as to form an electron source integration array with a high integration level, so that the on-chip electron source is enabled to have high overall emission current, and more application requirements are met. For example, the on-chip micro electron source provided by the invention can be widely applied to various electronic devices involvingan electron source such as X-ray tubs, microwave tubes and flat-panel displays.

This invention relates to a cathode preparation method for field emission display devices based on metal / nm tube composite plating including: pre-processing nm tubes to open its end and purify it then scattering or adding a dispersant to scatter the nm tubes in a plating basic solution then to prepare metal / nm tube gradient composite film at the assigned position of the cathode of the display device by a mask plating method then to erode the surface of the composite plating layer so as to release part of the nm tubes of the extreme layer from the metal cladding, finally cleaning the plating layer to form a metal / nm tube composite micro-structure with part bared and part implanted in the metal matrix.

A film field emission cathode with double insulated layers belongs to the technique area of vacuum electron emission type of flat display device. The invention incldues glass base plate, lower electrode layer, insulating layer and upper electrode layer. The insulating layer is composed of upper nad lower insulating films, usually the lower insulating layer is non-crystal insulating film and the upper insulating layer is crystal insulating film. The lower electrode layer can be composed of two layers of metal films or can be composed of a metal and semi-conductor film. The upper electrode layer can be composed of two layers of metal films or a metal and conductor film. The invention gives electron emissivity large than 0.5%. The non-crystal insulating film has property of high withstandingvoltage and long service life.

The invention discloses a symmetrical type carbon nanotube cathode ionization gauge. A carbon nanotube array capable of achieving electron field emission at room temperature is taken as a cathode, interferences of the high-temperature thermionic cathode to a heat sensitive, light sensitive and strong magnetic field system are overcome, and a power consumption demand is reduced based on a field emission mechanism. The carbon nanotube array cathode grows on two faces of a substrate, and symmetrical double-electrode arrangement is adopted; and, on the premise that the complexity of a circuit is not changed, the lengths of electron trajectories are effectively prolonged, and improvement of the sensitivity of an ionization gauge in the kind is facilitated. Furthermore, higher-voltage anodes 5 are added between gate electrodes 4 and collecting electrodes 6, so electrons oscillates between the gate electrodes 4 and the collecting electrodes 6, the electron trajectories are also prolonged, and the sensitivity of the ionization gauge is further improved.

This invention relates to a panel display with an umbrella grating array structure and its process technology, in which, the display includes a sealed vacuum cavity composed of a cathode panel, an anode panel and surrounding glasses, a photoetched anode conduction layer and a fluorescence powder layer on the conduction layer, a wall supporting structure and getter elements, in which, an umbrella grating array structure is prepared on the cathode panel and the control to electronic emission of the cathode is strengthened on the basis of fine field emission property of the cathode to reduce the working voltage of the device and increase its emission efficiency.

The invention discloses a dual-region tubular high-temperature electrostatic dedusting device. The tubular high-temperature electrostatic dedusting device comprises an electrical charge region and a dust collecting region, wherein the electrical charge region comprises an emitting cathode, an electrical charge anode circular tube and an electrical charge high-voltage power supply; an emitting cathode is suspended on the center of the electrical charge anode circular tube, and is connected with a cathode of the electrical charge high-voltage power supply, and the electrical charge anode circular tube is grounded; the dust collecting region comprises a dust collecting cathode, a dust collecting anode circular tube and a dust collecting high-voltage power supply; the dust collecting cathode is suspended at the center of the dust collecting anode circular tube, and is connected with a cathode of the dust collecting high-voltage power supply, and the dust collecting anode circular tube is grounded; the electrical charge anode circular tube is communicated with the dust collecting anode circular tube. On one hand, the device provided by the invention effectively utilizes the flue gas waste heat, and saves energy sources, and on the other hand, due to the high density of emitted current of the device, the collecting efficiency on dust, especially fine particles, is improved greatly.

The invention discloses a shaping device and method for a field emission electron source emitter tip. The shaping device comprises a vacuum chamber, a vacuum pumping system, a vacuum degree measuring system, an electronic gun assembly, a power source system and an electron beam imaging system. The method comprises the steps that the field emission electron source emitter tip is heated to be passivated, a critical electric field is applied to an anode to form field emission, the balance, on the surface, between the surface tension of the emitter tip and the electric field force produced by the additional electric field is achieved, and therefore shaping is achieved; after the field emission electron source emitter tip is shaped, a stable emission surface is formed on the emitter tip. The stable emission surface can make electronic beam current emitted by a field emission electron source have the advantages that the emission current is large, emission directions are concentrated, the density of angle current is high, monochromaticity is good, and beam current emission is stable.

The invention relates to a method for preparing a composite film for a cathode of a field transmission display device, belonging to nano material technical field, the method comprises preprocessing CNT and CNF, performing cut short, purification and surface modification for CNT and CNF; dispersing CNT or CNF in the base bath electroplated by Zn; depositing a Zn base carbon nano tube composite film and a Zi base carbon nano fiber composite film; leveling up the composite film using polishing and burnishing process; performing chemical etching for the composite film by an etching agent; depositing a seed layer electroplated by copper and chromium; electroplating required base metals (nickel, silver, gold and copper or the like); planting one part of CNT or CNF formed by muriate acid Zn, exposing the rest parts of that outside and evenly distributing the rest parts on the surface layer of the electrode for presenting ''planting cloth'' effect. The invention can be used for preparing high-performance field transmission devices.

A film field emission cathode with ingredient gradually changed in electron transport layer belongs to the technique area of vacuum electron emission type of flat display device, especially in relates to the structural design of plane type field emission cathode. The invention is composed of base plate glass, lower metal electrode, insulated layer with single component, electron transport layer and upper electrode. The medium film the ingredient gradually changed is adopted in electron transport layer, i.e. from button to top of the medium film, the ingredient of high electric affinity is changed to that of lower electric affinity. Metal or semiconductor film with lower work function is adopted in the upper electrode. The invention possesses features of large emissive current, long service life and lower cost. It is suitable for producing field emission type flat display device with large area.

The present invention discloses a nano cold cathode electron source with a dual gate-all-around structure, which comprises a substrate, an insulating layer, a bottom cathode electrode, a bottom segmented ring-shaped gate electrode, etched through holes, a top cathode electrode, a top ring-shaped gate electrode, a growth source film and a nanowire cold cathode. The top ring-shaped gate electrode isrespectively connected with the bottom segmented ring-shaped gate electrode through the etched through holes. A method for preparing the nano cold cathode electron source with the dual gate-all-around structure is also disclosed and comprises the following steps: the bottom cathode electrode, the bottom segmented ring-shaped gate electrode, the insulating layer, the etched through holes, the topcathode electrode and the top ring-shaped gate electrode are manufactured; the growth source film is deposited; and the nanowire cold cathode grows through thermal oxidation. The nano cold cathode electron source has the strong grid-controlled electron emission capability and the row-and-column addressable dual gate-all-around structure.

The invention discloses an X-ray source for X-ray raster differential phase-contrast imaging. The X-ray source comprises an annular cathode, an anode target, an electrode structure, a cathode heating power supply and an electrode structured power supply, wherein the annular cathode and the target surface of the anode target are arranged oppositely; an X-ray emitting window, which corresponds to the central position of the annular cathode and is parallel to the target surface of the anode target, is arranged at the back of the annular cathode; the target surface of the anode target is perpendicular to the optical axis of emitted X-rays; the electrode structure comprises a cathode sleeve and an anode sleeve; the anode target is arranged in the anode sleeve; the annular cathode is arranged in the cathode sleeve; an array structure formed by two different materials, which are alternated periodically, is arranged on the target surface of the anode target; the two different materials adopt two substances formed by two elements with large atomic number difference. The novel X-ray source has a relatively simple structure and is applied to high-energy X-ray phase-contrast imaging; the problem that the field of view is limited is thoroughly solved because the emitted X-rays are not distributed in the axial direction.

The invention discloses an external thermionic cathode distributed X-ray device. The X-ray device is provided with a vacuum box, multiple electron emission units, an anode and a power supply and control system, wherein the periphery of the vacuum box is sealed, the inside of the vacuum box is in a high vacuum state, the electron emission units are mutually independent and are arranged to form a linear array and installed on the side wall of the vacuum box, the anode is installed in the middle inside the vacuum box and is parallel to the arrangement lines of the electron emission units in the length direction, the anode and the installing plane for the electron emission units form a preset included angle in the width direction, and the power supply and control system is provided with a high-voltage power supply, a focusing power supply, an emission control device and a control system. Each electron emission unit is provided with a heating lamp filament, a cathode connected with the heating lamp filament, an insulation supporting part surrounding the cathode and the lamp filament, a focusing electrode located above the cathode and configured at the top end of the insulation supporting part and a connecting fixing part arranged above the focusing electrode and connected with the box wall of the vacuum box in a sealed mode, wherein a lamp filament lead penetrates through the insulation supporting part to be connected with the emission control device.

Provided are apparatus and method for generating distributed x-rays. A hot cathode of an electron gun (1) is used in vacuum to generate electron beams (10) having certain initial movement energy and speed. Periodic scanning is performed with the initial low-energy electron beams, which are thus caused to be reciprocally deflected. A current-limiting device (4) is provided in the travel path of the electron beams along the direction of the reciprocal deflection. Through holes arranged in an array on the current-limiting device, only part of the electron beams targeting specific positions can pass to form sequential electron beam currents distributed in an array. These electron beam currents are accelerated by a high-voltage electric field to obtain high energy, bombard the anode target (5), and thus sequentially generate corresponding focus spots and x-rays distributed in an array at the anode target.

The invention belongs to the field of crossing of a vacuum electronics technology and a novel carbon material technology and particularly relates to a graphene-based field emission cold cathode and apreparation method. The field emission cold cathode comprises a substrate and an emitter, wherein the substrate is taken as a conductive substrate and is a silicon wafer or a metal sheet; the emitteris a graphene film layer; the graphene film layer is in close contact with the substrate; the thickness of the graphene film layer is 20-180 microns; and the graphene film layer is formed by grapheneclusters of which the particle sizes are 15-45 microns. The graphene-based cold cathode provided by the invention can be prepared by using the method, is in an array form, has good performance advantages of a low starting electric field, a low threshold electric field and high emission current, and can be applied to the fields, such as field emission display (FED) as an excellent electronic source.

The invention provides a processing method of a field emitting cathode. The processing method of the field emitting cathode comprises the following steps of: preparing an MWCNT (Multi Walled Carbon Nano-Tube) by using a chemical vapor deposition method; ultrasonically diffusing purified MWCNT powder in absolute ethyl alcohol, naturally drying at a room temperature and sufficiently grinding, and mixing with an organic carrier and using as cathode slurry after stirring for 1-2 hours; printing a layer of silver slurry thin film electrode with an area of 60 mm*25 mm on a glass substrate; printing a carbon tube thin film at the center of the substrate by the prepared carbon tube slurry through a 200-mesh silk screen after sintering; putting all samples in a tube type furnace together, and sintering at the presence of Ar; and carrying out laser ablation treatment for 5 minutes in air by using an excimer laser system. Therefore, the switch-on field intensity is reduced, and the emitting current is increased.

A magnto transducer consists of bottom base, the first metal film, the first insulation film, the second metal film, the second insulation film, the third metal film, isolator, top base, positive electrode and insulation film as well as film located at centre of the first metal film and used as electron source of field emission. The film can be made by carbon nanotube film or by diamond film.

The invention provides a hot cathode-based gas discharge electron source, which can be quickly started, has low power required for the operation, and has a wide coverage range of emission current. Anemitter is directly heated by using a heating wire, a heat shielding component and an anode cover are additionally arranged outside a cathode, and the heat shielding component increases the thermal efficiency of the cathode and reduces the environmental requirements during the operation of the cathode; the anode cover can reduce the influence of external environment particle sputter etching on theemitter and prolong the service life of the emitter, and the anode cover also provides a discharge chamber for gas discharge, can absorb electrons in a discharge plasma and maintain the gas discharge, and can also restrain the directionality and size of the emitted electrons and improve the working efficiency of an electron source; and in addition, according to the scheme of the invention, a gassupply pipeline is arranged in the electron source for adding working medium gas to the gas discharge chamber, and by adding the working medium gas during the operation of the cathode, the emission current of the cathode can be effectively increased, and the coverage range of the emission current of the cathode can be extended.

The invention provides a field emission negative electrode structure with current-limiting PN junctions. The field emission negative electrode structure comprises a substrate, a conductive layer above the substrate, a P type semiconductor layer above the conductive layer, an N type semiconductor layer above the P type semiconductor layer and negative electrode emitters above the N type semiconductor layer, wherein a PN junction is formed by the P type semiconductor layer and the N type semiconductor layer; and the PN junction is in a reverse bias state when the negative electrode is in use. According to the field emission negative electrode structure, based on the characteristic that when the PN is under a certain reverse bias voltage, the flowing current barely changes along with the changes of the reverse bias voltage, one PN junction is connected below each emission unit in the filed emission array in series, so that the emission current of each unit is balanced; therefore, the stability and the uniformity of the emission current of the field emission negative electrode array are improved; the burnout of a part of the emitters caused by overhigh loads is avoided; the service life of the device is prolonged; and the general emission capability of the negative electrode is improved.

The invention discloses a sheet electron beam generation cathode for a vacuum electronic device. The cathode comprises a conductor sheet, wherein the width, the thickness and the length from the front end to the rear end of the conductor sheet are proper, and meet the design requirements of the vacuum electronic device. When higher voltage is applied, an electric field at the front end of the conductor sheet is high in intensity, electrons are withdrawn from the conductor sheet, plasmas are generated at the front end of the conductor sheet when the applied voltage is further increased, and higher current is withdrawn from the plasmas by the high-intensity electric field to form sheet electron beams. When the current is higher, the current withdrawn from the plasmas flows forwards along a magnetic line of force, and an inclined surface body is impacted by the backwards-flowing current; from the point of energy, the potential is unchanged when the inclined surface body is impacted by the backwards-flowing current, so that energy loss is avoided. The sheet electron beam generation cathode for the vacuum electronic device has the characteristics of high efficiency and high current, and also has the advantages of low cost and easiness in machining and assembly.

The invention provides an external thermionic cathode distributed X-ray device, comprising a vacuum box which is sealed all around and is highly vacuum inside, a plurality of electronic emission units, an anode, and a power and control system. Each electronic emission unit is independent to each other and the electronic emission units are arranged in a linear array and are installed on the side wall of the vacuum box. The anode is installed in the middle part of the vacuum box. On the length direction, the anode is parallel to the arrangement line of the electronic emission units, and on the width direction, an included angle in a preset angle is between the anode and the installation plane of the electronic emission units. The power and control system is provided with a high-voltage power supply, a focusing power supply, an emission control device and a control system. The electronic emission unit is provided with a heating filament, a cathode connected with the heating filament, an insulating support piece which surrounds the cathode and a filament, a focusing electrode which is configured on the top end of the insulating support piece in a manner of being above the cathode, and a connecting fixing piece which is configured above the focusing electrode and is connected with the box wall of the vacuum box in a sealed manner. The filament lead passes through the insulating support piece and is connected with the emission control device.

The invention relates to a silicon carbide junction barrier Schottky diode suitable for a high-temperature environment, and belongs to the technical field of semiconductor devices. According to the device, a novel P + region injection layout structure is adopted on the basis of a traditional JBS device structure, the area of a Schottky contact region and Schottky junction current are increased, meanwhile, the area of a depletion region is increased through a strip-shaped pattern of the P + injection region, the current decline and power loss increase of a silicon carbide junction barrier Schottky diode at high temperature are reduced, and the performance of the device is improved. And the reverse breakdown voltage is prevented from being reduced after the Schottky region of the diode is increased, and the problems that the forward working current of the JBS device declines seriously and the power loss is obviously increased in a large-current and high-temperature working environment are solved.

The invention relates to the technical field of vacuum electronics, in particular to a storage type ion source, which comprises a cathode, an electron focusing system, an ionization chamber and an electron collector; the electron focusing system is arranged above the cathode, and electrons generated by the cathode form an electron beam current through the electron focusing system; the ionization chamber is arranged between the electron focusing system and the electron collector, grid meshes are arranged on the two sides of the ionization chamber, and a uniform electric field is formed betweenthe ionization chamber and the grid meshes; the electron beam current is ionized by the uniform electric field and then is received by the electron collector. Ions are trapped and stored by utilizingthe space charge effect of electrons, so that the initial states of the ions have good consistency, and the stability and uniformity of an ion beam are greatly improved when an ion source is led out.

The invention belongs to the field of microwave, millimeter wave and terahertz frequency band electric vacuum devices, and particularly provides a multi-pole multi-electron injection radiation sourcebased on a cold cathode. The device mainly comprises a cathode baffle, a radiation source core, a feed system, a metal shell and an output window sheet; the relatively high high-frequency field at themiddle part of a high-frequency structure is fully utilized to act on the surface of the cold cathode through a multi-stage emission and multi-pole modulation mode, so that the emission current is increased and the electron injection modulation depth is deepened, so that the electronic injection has a remarkable pre-modulation effect. According to the method, a very high-quality field emission pre-modulation electron injection can be obtained, the wave-injecting interaction efficiency is obviously improved, and the output power is obviously improved; the complexity of the device is greatly reduced without an optical-optical system, and fine processing is carried out, the size of the device can reach the micron order, and the integration and miniaturization of millimeter wave, sub-millimeter wave and terahertz radiation sources are realized.

The invention discloses an underwater middle and long distance electric field communication system based on FSK modulation and demodulation, which is characterized in that an MCU is arranged at a transmitting end, adopts a 2FSK signal modulation and demodulation mode for communication and can transmit a serial port signal to an FPGA logic controller for signal modulation, and the modulated signal is subjected to digital-to-analog conversion and signal amplification and then is transmitted to an underwater channel through a transmitting electrode; signals emitted by the emitting electrode are received through the receiving electrode, are amplified, filtered and re-amplified in sequence, then are subjected to analog-to-digital conversion processing and then are input into the FPGA logic controller to be demodulated, the demodulated signals are transmitted into the MCU of the receiving end to complete communication, and the emitting end and the receiving end are respectively connected with a power management module. The system is suitable for communication between underwater communication equipment with small volume and low power consumption.