166results about "Transit-tube electron/ion guns" patented technology

A cold field emission (CFE) electron source for a focused electron beam system such as a transmission electron microscope (TEM), scanning transmission electron microscope (STEM), or scanning electron microscope (SEM) is disclosed. The source employs an emitter enclosure electrode behind the CFE tip which, in conjunction with the extractor electrode, defines a closed volume that can be thoroughly cleaned by electron impact desorption (EID) and radiative heating from a heated filament located between the emitter enclosure electrode and extractor electrode. The extractor electrode may have a counterbore which restricts backscattered electrons generated at the extractor from reaching portions of the source and gun which have not been cleaned by EID. Pre-cleaning of the emitter enclosure electrode and extractor electrode prior to cold field emission substantially improves both source emission stability and frequency noise characteristics, enabling source operation over time intervals adequate for application to TEMs, STEMs, and SEMs.

The invention provides a dual-electron-beam terahertz wave radiation source. The terahertz wave radiation source adopts an overmode cascading folded waveguide traveling-wave amplified high frequency structure, so that the length of a single-section folded waveguide slow-wave structure can be dramatically shortened, and the demand on the magnetic field is reduced. The terahertz wave radiation source adopts the dual-electron beam excitation mode, so that the output power can be improved, and the demand on the negative electrode current emitting density is reduced as well; the input signal adopts a higher mode TE20 mode, so that the dimension of the slow-wave structure can be enlarged, and the processing of the slow-wave structure can be performed conveniently; within the same terahertz wave radiation source, the high power terahertz wave output is realized, and the design and the processing of the terahertz wave radiation source are facilitated; and therefore, the applications of the terahertz wave radiation source in the anti-interference, harmful substance detection, ultra wide band radar long-distance detection and high-resolution imaging radar and the like are promoted.

This disclosure describes a multibeam doubly convergent electron gun. Two or more beamlets can be run parallel to the axis at a prescribed radius to produce sufficient current to drive the VED. In order to obtain sufficient cathode surface area to provide the required current, the beamlets are launched from a cathode radius greater than the radius required in a slow wave circuit. In one embodiment, an electron gun includes a focus electrode that surrounds two or more cathodes, wherein each cathode emits a beamlet comprised of a plurality of electrons directed to a predetermined location. A first anode receives each beamlet at the predetermined location, accelerates each beamlet and changes the radius of each beamlet. A second anode receives each beamlet from the first anode, directs each beamlet along a predetermined axis, further accelerates, and can further compress each beamlet.

A cathode-adjustable single anode magnetic control electron gun belongs to a single anode magnetic control electron gun that is used in conjunction with a vacuum gyrotron, and comprises an electron gun casing, a base, an electric heating wire component, a support cylinder, a regulating mechanism assembly, an electron gun cathode, a fixed annular plate, an anode and a retainer ring, wherein, the electric heating wire component comprises an electric heating wire, an electric heating wire sleeve and insulating fillers, and the electric heating wire sleeve is provided with a ring-shaped scale section, a threaded section and a guiding plane surface; the regulating mechanism assembly is arranged between the electric heating wire sleeve and the support cylinder thereof, and comprises an adjusting screw nut; in addition, the cathode-adjustable single anode magnetic control electron gun can adjust the distance between the cathode and anode according to the operating condition, the transverse to longitudinal velocity ratio of an obtained electron beam is greater than 1.0, and the longitudinal velocity spread is less than 2 percent. Therefore, the influence caused by assembly error and overheating deformation or great current and voltage variation of the electron gun can be overcome effectively, and the cathode-adjustable single anode magnetic control electron gun is characterized in that working current and voltage capable of adapting to wider range can be achieved, the discreteness of the electronic longitudinal velocity is low, the performance of the electron beam is excellent, and the power and the efficiency for later beam-wave interaction of the gyrotron can be improved and so on.

The invention relates to a compact oscillator based on a cold cathode. The compact oscillator based on a cold cathode includes a high frequency interaction system, a cold cathode electron gun which isin sealed connection with one end of the high frequency interaction system, a collection electrode which is in sealed connection with the other end of the high frequency interaction system, and a signal output module which is arranged on the high frequency interaction system and is in sealed connection with the high frequency interaction system, wherein the high frequency interaction system includes a tubular housing and a periodic slow wave structure on the inner wall of the tubular housing; the cold cathode electron gun includes a cold cathode emitter, and the cold cathode emitter is arranged in a cavity which is formed by the high frequency interaction system and the cold cathode electron gun; by directly integrating the cold cathode with the inside of the high frequency interaction system, the compact oscillator enables the high frequency field to directly act on the surface of the cathode to obtain a modulation electron beam; the modulation electron beam can improve the beam-waveinteraction efficiency and gain so as to reduce the period number of the periodic slow wave system so as to reduce the size of the high frequency interaction system; and generation of the modulationelectron beam can also reduce the oscillation-starting time.

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.

The invention belongs to an oval sheet beam electron gun, which is used with a travelling wave tube, a backward wave tube and the like. The oval sheet beam electron gun comprises a shell, an electric heating wire in the shell, a cathode component, a focusing electrode component and an anode, wherein an emitting surface of a cathode head of the cathode component is a plane, the focusing electrode component comprises a pyramidal focusing hole, and the anode is positioned at an output port of the shell and provided with an anode hole which is a cylindroid hole. The cathode head is made of lanthanum hexaboride, the emitting surface of the cathode head is modified into a plane, a pyramidal hole with a rectangular axial section is used as the focusing hole, and the cylindroid hole is used as the anode hole, so that the oval sheet beam electron gun has the advantages that the oval sheet beam electron gun is simple in structure and convenient in processing, the precision is easy to be guaranteed, devices are easy to be miniaturized, the production cost is low, current emitted by the cathode head is high in density, operation frequency of the devices and current density of electron beams can be improved effectively, the electron gun is high in output efficiency and long in service life, and the like. The defects of complex structure, low current density and unevenness of the electron beams, high evaporativity and short service life of the cathode in operation at high temperature, and the like in the prior art can be overcome.

A multi-beam electron gun provides a plurality N of cathode assemblies comprising a cathode, anode, and focus electrode, each cathode assembly having a local cathode axis and also a central cathode point defined by the intersection of the local cathode axis with the emitting surface of the cathode. Each cathode is arranged with its central point positioned in a plane orthogonal to a device central axis, with each cathode central point an equal distance from the device axis and with an included angle of 360 / N between each cathode central point. The local axis of each cathode has a cathode divergence angle with respect to the central axis which is set such that the diverging magnetic field from a solenoidal coil is less than 5 degrees with respect to the projection of the local cathode axis onto a cathode reference plane formed by the device axis and the central cathode point, and the local axis of each cathode is also set such that the angle formed between the cathode reference plane and the local cathode axis results in minimum spiraling in the path of the electron beams in a homogenous magnetic field region of the solenoidal field generator.

The invention discloses a K-wave-band high-efficiency continuous wave space travelling wave tube. The travelling wave tube comprises a double anode electron gun (1), a slow-wave circuit (2), a periodic permanent magnetic focusing system (6) and a level-four voltage reduction collector (3), wherein the slow-wave circuit (2) is connected to the double anode electron gun (1); the periodic permanent magnetic focusing system (6) is installed on a periphery of the slow-wave circuit (2); and the level-four voltage reduction collector (3) is connected to the slow-wave circuit (2). Two ends of the slow-wave circuit (2) are connected to an input waveguide (4) and an output waveguide (5). By using the K-wave-band high-efficiency continuous wave space travelling wave tube, the structure is designed reasonably, electronic efficiency is high, collector efficiency and total efficiency are high too, and performance is stable.

An electron beam source for use in an electron gun. The electron beam source includes an emitter terminating in a tip. The emitter is configured to generate an electron beam. The electron beam source further includes a suppressor electrode laterally surrounding the emitter such that the tip of the emitter protrudes through the suppressor electrode and an extractor electrode disposed adjacent the tip of the emitter. The extractor electrode comprises a magnetic disk whose magnetic field is aligned with an axis of the electron beam.

A radio frequency magnetron device for generating radio frequency power includes a cathode at least partially formed from a diamond material. An anode is disposed concentrically around the cathode. An electron field is provided radially between the anode and the cathode. First and second oppositely charged pole pieces are operatively connected to the cathode for producing a magnetic field in a direction perpendicular to the electric field. A filament is provided within the electron tube which when heated produces primary electrons. Alternatively, a voltage is applied to the anode which causes primary electrons to emit from the diamond coated cathode. A portion of the primary electrons travel in a circular path and induce radio frequency power. Another portion of the primary electrons spiral back and collide with the cathode causing the emission of secondary electrons. The secondary electron emission sustains operation of the magnetron device once the device has been started.

An electron beam source for use in an electron gun. The electron beam source includes an emitter terminating in a tip. The emitter is configured to generate an electron beam. The electron beam source further includes a suppressor electrode laterally surrounding the emitter such that the tip of the emitter protrudes through the suppressor electrode and an extractor electrode disposed adjacent the tip of the emitter. The extractor electrode comprises a magnetic disk whose magnetic field is aligned with an axis of the electron beam.

The invention discloses a double electron beam electron gun and a gyrotron. The double electron beam electron gun can produce two beams of electron beams and comprises a first anode, a first cathode and a second cathode, wherein the first cathode is under the action of a voltage between the first cathode and the first anode and generates a first electron beam, and the second cathode is under the action of a voltage between the second cathode and the first anode and generates a second electron beam. The electron gun with double cathodes not only can be applied in the field of gyrotron, but also can be applied in other fields of the microwave industry.

The invention provides a double electron beam THz wave radiation source of a cascade high-frequency structure. The double electron beam THz wave radiation source uses a backward wave oscillator to generate THz signals as drive signals of a travelling wave amplifier. In a same THz wave radiation source, high-power THz waves are generated and at the same time the power amplification and band spread of the THz waves are realized, thereby being beneficial for applying the THz wave radiation source in anti-interference, harmful substance detection, ultra wide band radar long-range detection and high resolution imaging radar aspects, etc.

The invention discloses a dual-mode multi-beam electronic gun for a dual-mode traveling wave tube and a method for controlling the dual-mode multi-beam electronic gun. The dual-mode multi-beam electronic gun comprises a cathode, a shade gate, an internal grid, an external grid and an anode, which are arranged in sequence, wherein the cathode comprises a cathode molybdenum tube, the inside of which is divided into two parts along the axis of the cathode molybdenum tube; the two parts are separated by insulating ceramic; a cathode sponge body is mounted in one part, and a filament filling and sealing insulator is mounted in the other part and is internally provided with a filament; the end face of the cathode molybdenum tube is provided with a plurality of holes; the internal grid controls the electronic beams in partial holes, and the external grid controls the electronic beams in the rest holes so as to implement dual-mode operation. According to the dual-mode multi-beam electronic gun and the method, a high-mode operation state and a low-mode operation state can be provided, and the control voltage is consistent, so that the electronic beams in two modes can be focused by the same magnetic field.

The invention provides a terahertz source amplifying device based on a multiple-cascade high-frequency structure. The terahertz source amplifying device is a cascaded multi-electron-beam terahertz radiation source combining a backward wave amplifier and a traveling wave amplifier. A THz excitation signal is input to the backward wave amplifier and is amplified through backward wave electron beam-wave interaction, a backward wave signal is output to a traveling wave high-frequency structure through dual ports, multistage amplification and band broadening are realized through multiple beam-wave interaction at a traveling wave section, and power synthesis is carried out on signals output by the multiple-cascade structure. The terahertz source amplifying device based on multiple-cascade high-frequency structure has the characteristics of high power, high gain and wide band, has absolute advantages in implementing a THz integrated vacuum electronic device and has important application prospects in aspects such as THz radar, communication, danger detection and imaging.

The invention belongs to a dual-anode magnetic control electronic gun for being matched with a vacuum gyrotron. The dual-anode magnetic control electronic gun comprises an electronic gun shell, a base, an electric heating wire assembly, a supporting drum, an adjusting mechanism assembly, an electronic gun cathode, a fixed annular plate, a first anode, a fixed ring and a second anode, wherein the electric heating wire assembly comprises an electric heating wire, an electric heating wire bushing and insulation stuffing, the electric heating wire busing is provided with an annular scale section, a threaded section and a guide plane, the supporting drum is provided with a sliding-type positioning sleeve and fixes the electric heating wire assembly into the electronic gun shell, the adjusting mechanism assembly with an adjusting nut is arranged between the electric heating wire bushing and the supporting drum; and a distance between the cathode and anodes is adjusted according to a working condition, a transverse-longitudinal speed ratio of an obtained electron beam is greater than 1.0, and the dispersion of the longitudinal speed is smaller than 1.5 percent. Due to adopting the dual-anode magnetic control electronic gun with adjustable cathode, the influences of a traditional electronic gun caused by assembling error, overheating deformation or large current and voltage variation can be effectively overcome. The dual-anode magnetic control electronic gun has characteristics of adaptability to the working current and voltage of greater range, low dispersion of the speed, excellent performance of electron beams, capability of improving the interaction power and efficiency of the subsequent gyrotron electron beams and the like.

The invention provides an electronic gun of a traveling-wave tube. The electronic gun comprises a cathode, a cathode supporting component, a gun shell component, a control electrode and an anode. The diameter length of the cathode is 1 mm to 10 mm, the height of the cathode is 1 mm to 10 mm, and the weight of the cathode is 0.02 g to 2 g. The cathode is composed of a cathode head and a heating component, and the cathode head is made from a barium and tungsten material with the diameter being 1 mm to 10 mm, the height being 1 mm to 5 mm and the weight being 0.01 g to 1 g. The heating component is composed of a heater, a cathode cylinder and insulation media. The heater is formed by winding a tungsten filament or a tungsten-rhenium filament or a high-rhenium filament with the diameter being 0.01 nn to 1 mm, the cathode cylinder is made from a molybdenum and / or tungsten material with the thickness being 0.02 mm to 0.2 mm, the position between the heater and the cathode cylinder is filled with the insulation media which are formed by burning alumina powder, and the control electrode and the anode are electronic optical focus components of the electronic gun. The electronic gun improves heating efficiency of the cathode.

The invention discloses a high-assembly-accuracy grid-control electronic gun which comprises a cathode hot wire component, a heat shield combination, a supporting cylinder combination, a control grid combination, a shadow grid combination, a gun shell combination and a magnetism shield welding cylinder combination. The electronic gun is reasonable in design, assembling parts of the electronic gun are screened out through a large number of experiments, and the electronic gun with high accuracy is obtained by assembling. The electronic gun is long in service life and high in reliability and stability, a specific-shaped electron beam can be provided for a coupled cavity traveling-wave tube, the assembling requirement of the high-standard coupled cavity traveling-wave tube can be well met, and the shortcomings of the prior art can be overcome.

The invention belongs to a coaxial dual-electron beam electron gun assorted with a gyrotron (an oscillator and an amplifier), which comprises an electron gun barrel body, a base, a cathode sleeve with an electric heating wire and two electron beam emitting rings, internal and external anodes and a control anode. In the coaxial dual-electron beam electron gun, the internal and external anodes and the cathode sleeve are arranged oppositely and coaxially, the internal anode and the external anode are still arranged in an overlapping (telescopic) way, and the control anode is also arranged between the internal and external anodes and a cathode head to regulate the current of an electron beam and the rotation speed and axial speed of the electron beam in the gyrotron. Therefore, the invention has the characteristics that: output power can be regulated quickly, work efficiency of the gyrotron also can be regulated arbitrarily within the range of the peak efficiency of the gyrotron, the performance of the coaxial dual-electron beam electron gun and the application range of the gyrotron assorted with the electron gun are improved effectively, breakdown between the internal and external anodes and the cathode sleeve and between the control anode and the cathode sleeve is prevented, the coaxial dual-electron beam electron gun is favorable for the miniaturization of devices, and the like.

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.

A cold field emission (CFE) electron source for a focused electron beam system such as a transmission electron microscope (TEM), scanning transmission electron microscope (STEM), or scanning electron microscope (SEM) is disclosed. The source employs an emitter enclosure electrode behind the CFE tip which, in conjunction with the extractor electrode, defines a closed volume that can be thoroughly cleaned by electron impact desorption (EID) and radiative heating from a heated filament located between the emitter enclosure electrode and extractor electrode. The extractor electrode can be provided with a countersink which restrains backscatter electrons generated by an extractor from arriving parts of arriving sources and guns not cleaned by EID. Precleaning of an emitter enclosing electrodes before cold field-emission and extractor electrodes substantially improves both source emission stability and frequency noise characteristics, thereby realizing source operation with enough time interval for the application of TEM, STEM and SEM.

The invention relates to the technical field of vacuum electronic devices, and discloses a double-grid control type cold cathode electron gun and a preparation method thereof. In accordance with the present invention, A simple, a new type of electron gun with long service life and excellent performance is provided, the cold cathode is used as the emission source of the vacuum electronic device, Asurface of the cold cathode is arrayed by a cathode grid, which can effectively weaken the electrostatic shielding effect of electron emitted by large area cold cathode material, the emission currentof large area cold cathode material is increased, At the same time, the surface of the cathode substrate is designed as a whole plane so as to not only avoid machining burr and other problems, improveedge effect and spark phenomenon, but also make the electric field distribution on the surface of cathode substrate flat, which is conducive to improving the uniformity of emission current density and achieving the purpose of large current emission, so the electron gun can be used in vacuum electron radiation components or devices that generate large current and high density electron beam.

To stabilize an emission current of cold cathode electron gun and extend its product life. A cold cathode electron gun comprises a cold cathode for emitting electrons by field-emission, a gate electrode for controlling the field-emission, a Wehnelt electrode which surrounds the cold cathode and the gate electrode, a first anode for accelerating electrons, and a second anode for constructing an electron lens together with the first anode. An inner diameter of the first anode is greater than a radius of flow of electrons which are emitted in the direction perpendicular to the optical axis of the electron lens.

The present invention discloses a heater structure of magnetron injection gun, which relates to microwave technology. The heater is formed by the circular ring circled by spiral cylindrical tungsten filaments or rhenium tungsten filaments. First structure of the heater is that two semicircles are formed by spiral cylindrical tungsten filaments or rhenium tungsten filaments; the two ends of each semicircle are provided with a bar-shaped lead; and a circular ring is then formed by fixedly connecting the four bar-shaped leads in pairs. The second structure is that the spiral cylindrical tungsten filaments or rhenium tungsten filaments are shaped into a circular ring, of which the two ends are provided with straight-bar-shaped leads having a clearance arranged therebetween. The heater structure of the present invention is applicable to various magnetron injection guns of gyrotron, and the processing technology is easy and convenient. Moreover, the heater is high in heating efficiency and is unlikely to bring about short-circuit failure.

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. An optional post-accelerator may be located between the modulator and the output circuit for increasing energy of the electron beam exiting the interceptor aperture.

The invention discloses an external gate-controlled cold cathode array electron gun. The problems in the prior art such as poor accuracy, poor pressure resistance of devices, poor stability and complex process are solved. The external grid-controlled cold cathode array electron gun comprises a cathode base, a cathode substrate fixed to the cathode base, a cold cathode emission unit array arranged on the upper end face of the cathode substrate and having a slot, and an electron gun shell of which the upper end part is open and the lower end is connected to the cathode base and sealed. The inside of the electron gun shell is hollow. The electron gun shell is composed of a lower sleeve and an upper sleeve, a gate fixing lower base with a through hole in the middle is arranged between the lower sleeve and the upper sleeve, an external gate is mounted on the gate fixing lower base, and a gate fixing upper base is arranged on the external gate. The external gate can move up and down relative to the electron gun shell so that the distance between the external gate and the cathode substrate can be adjusted. The external gate-controlled cold cathode array electron gun of the invention has the advantages of simple manufacturing process, high precision, good consistency, and the like.

An electron emission device includes an anode, a cathode, an electron emitter structure, and an electron extraction electrode. The cathode is spaced from the anode. The electron emitter structure is electrically connected to the cathode. The electron extraction electrode is insulated from the cathode. The electron extraction electrode defines a through hole surrounded by a sidewall, and the electron emitter structure faces to the sidewall. The electron emitter structure includes a number of electron emitters extending toward the sidewall, each of the number of electron emitters includes an electron emission terminal, a first distance between each electron emission terminal and the sidewall is substantially the same, a second distance between the electron emission terminal and the anode is greater than or equal to 10 micrometers and smaller than or equal to 200 micrometers, and a pressure in the electron emission device is smaller than or equal to 100 Pascal.

An electron beam gun for a high power RF vacuum device has components joined by a fixed kinematic coupling to provide both precise alignment and high voltage electrical insulation of the components. The kinematic coupling has high strength ceramic elements directly bonded to one or more non-ductile rigid metal components using a high temperature active metal brazing alloy. The ceramic elements have a convex surface that mates with concave grooves in another one of the components. The kinematic coupling, for example, may join a cathode assembly and / or a beam shaping focus electrode to a gun stem, which is preferably composed of ceramic. The electron beam gun may be part of a high power RF vacuum device such as, for example, a gyrotron, klystron, or magnetron.

The present invention generally relates to systems and methods for generating controllable beam of electrons by using a hollow-cathode triode electron gun that substantially mitigate impact of back-streaming electrons.