66results about "Tubes with velocity/density modulated electron stream" patented technology

The invention discloses a distribution terahertz oscillator, which relates to technique of THz (terahertz) electromagnetic wave sources and comprises an electron gun, an interaction region and a collector. The interaction region consists of a periodic slow wave structured modulation resonant cavity and an energy extraction cavity, and the modulation resonant cavity is in a periodic slow wave structure which can be operated in a backward wave mode or a forward wave mode to be interacted with electron beams in a distributive manner, so that the electron beams can be modulated in terms of speed and density. The distribution terahertz oscillator integrates advantages of a backward wave tube and a distribution klystron, and has the advantage of suitableness for generating THz electromagnetic waves.

A pulse source generates both terahertz radiation (T-rays) and X-rays consecutively at high peak intensity using the same electron beam generated in an RF photoinjector and two different extractors/radiators for the T- and X-rays.

The invention discloses a terahertz radiation source based on a special Smith-Purcell effect. The terahertz radiation source comprises an electronic gun (1), metal rectangular gratings (3), a collector (4), a metal flat reflector (6) and an output port (8), wherein the electronic gun (1) is opposite to the collector (4), the metal rectangular gratings (3) are arranged between the electronic gun (1) and the collector (4), the metal flat reflector (6) is disposed above the metal rectangular gratings (3), and the output port (8) is arranged at the metal flat reflector (6). According to the invention, the oscillation-starting current density of an electron beam can be substantially reduced, through adjusting the distance from the reflector to the gratings, the terahertz radiation source can work at a lowest mold or a secondary mode in a controllable way, the structure is simple, required work voltages are low, huge external additional equipment is unnecessary, and miniaturization and integration are quite easily realized.

A microscale vacuum electronic device (10) provides for a mechanical modulation of cathode (12) position allowing improved high-frequency modulation of an electron beam (24) useful for vacuum electronic devices such as klystrons, klystrodes, and high frequency triodes.

The invention discloses a radial structure continuous wave terahertz oscillator, comprising a annular metal top board, a radial transmission electronic beam, a slow wave structure, a metal transition waveguide inner cylinder, a metal transition waveguide outer cylinder, a coaxial output waveguide and a solenoid; a radial transmission electronic beam performs mutual reaction with a high frequency mutual reaction area constituted by the annular metal top plate and the slow wave structure under the guiding of a radial uniform magnetostatic field to convert the kinetic energy of the electronic beam to an electronic wave in the terahertz frequency band; finally, the radial transmission electronic beam is hit to the metal transition waveguide inner cylinder to be absorbed; and the terahertz frequency band electromagnetic wave is transmitted out through the coaxial waveguide. Because the radial structure continuous wave terahertz oscillator adopts the radial structure and the size of the electronic beam and the integral size of the radial structure continuous wave terahertz oscillator are increased, the output power of the radial structure continuous wave terahertz oscillator is improved and the processing difficulty is reduced.

The invention discloses a terahertz gyrotron gallery mold backward wave interaction circuit and a control method thereof. According to the circuit and the control method, two gradation structures areled into a main cavity body, so that the nonuniformity of the circuit is improved; the cut-off frequency of a main high angular index competition mode is higher than that of an operating mode, so thata start oscillation characteristic of the circuit is that the circuit is particularly sensitive to a nonuniform circuit in a single-cavity oscillation state; a start oscillation current curve is greatly improved and effectively inhibited; and single-mode stable high-efficiency output of a high-order gallery operating mode is achieved. The circuit can specifically inhibit mode competition nearby the high-order gallery mode in a terahertz gyrotron backward wave oscillator; the operating stability and the operating efficiency of the gyrotron backward wave oscillator can be improved; and the significance from microwave and millimeter wave bands to a terahertz wave band is important for the gyrotron backward wave oscillator.

A self-assembling element fabricated using integrated circuit techniques may provide a small diameter helical conductor surrounding an electron beam for the construction of a vacuum electronic device such as a traveling-wave tube for terahertz scale signal.

The invention discloses an axisymmetric periodic permanent magnet focusing system with a prominent third spatial harmonics. The system comprises a plurality of permanent magnet focusing units with thelengths of L, each permanent magnet focusing unit comprises in order from left to right: a first magnetic pole (1); a first permanent magnet (2) having an N pole connected to the first magnetic pole(1); a second magnetic pole (3) connected to the S pole of the first permanent magnet (2); and a second permanent magnet (4) having an S pole connected to the second magnetic pole (3). The axisymmetric periodic permanent magnet focusing system with a prominent third spatial harmonics achieves the required peak axial magnetic field intensity Bm under the condition that the period L of the periodicpermanent magnet focusing system is not reduced, and simultaneously suppresses the fluctuation of the radius of an electron beam by utilizing the third spatial harmonics of the magnetic field distribution of the periodic permanent magnet focusing system on the axis, so that the aim of maintaining the stable passing of the electron beam is achieved.

The invention discloses a method for inhibiting grid emission of a pulsed travelling wave tube, relates to a microwave electric vacuum technology, and states an improvement measure for effectively inhibiting grid thermionic emission (grid emission for short) of the pulsed travelling wave tube, namely a novel hafnium (Hf) material is used as the material of a grid net in a pulsed travelling wave tube electronic gun. The metal has the properties of high work function, low secondary electron yield and high melting point/ low saturated steam pressure; and a diode test and tests of physical analysis, tube preparation application and the like of the metal show that the hafnium metal foil serving as a grid net substrate material can inhibit grid emission of the conventional pulsed travelling wave tube during the operating life, so that the operating reliability and the operating stability of the grid-controlled pulsed travelling wave tube is powerfully guaranteed.

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 invention discloses a harmonic gyrotron employing DC coil for magnetism supply, and belongs to the technical field of gyrotrons. The gyrotron comprises a magnetic control electronic gun, a resonant cavity, a quasi-optical mode converter and a collector, which are sequentially connected. The gyrotron also comprises the DC coil for supplying magnetism to a resonant cavity. The DC coil comprisesa magnet yoke part, and the magnet yoke part comprises a first magnet yoke sleeve and a second magnet yoke sleeve which are arranged on the periphery of the resonant cavity in a sleeving mode. The first magnet yoke sleeve and the second magnet yoke sleeve are arranged at an interval and fixedly connected with the resonant cavity. The direction of a magnetic line loop, outside the magnet yoke part,of the DC coil is from the first magnet yoke sleeve to the second magnet yoke sleeve. According to the invention, a superconducting magnet in the traditional harmonic gyrotron is replaced by the DC coil; meanwhile, thereby improving the start sped of the gyrotron. Meanwhile, the magnet yoke sleeves are arranged on the periphery of the resonant cavity of the gyrotron in a sleeving mode, the magnetic field generated by the DC coil is restrained and concentrated in the resonant cavity, the invalid field magnetic space is reduced, the magnetic supply efficiency of the DC coil is improved, and thepower consumption of the DC coil is reduced.

The invention discloses a lateral side cooling structure for a drift section of a sheet beam klystron and relates to the microwave technology. The drift section comprises an upper wall of the drift section and a lower wall of the drift section; the upper wall and the lower wall of the drift section are axially provided with square through slots; the square slots in the upper wall and the lower wall are axially and fixedly connected in parallel, so that a through hole is formed between two square slots; an n-shaped lateral plate is respectively arranged on each of the left side and the right side of the drift section, and the two n-shaped lateral plates are open outwards; the external axes of the two n-shaped lateral plates are respectively crossed and fixedly connected with the left side and the right side of the drift section to form a drift section main body; the openings of the n-shaped lateral plates at two sides of the drift section main body are fixedly connected with an internal side of a lateral cold water cover plate; a water path is formed between the lateral cold water cover plate and the lateral plate; the external side of the lateral cold water cover plate is perpendicularly and fixedly connected with two water nozzles; a water path end cover is respectively installed at two ends of the water path formed between the lateral cold water cover plate and the lateral plate, and two end ports of the water path are fixedly connected in a sealing manner. The invention solves the cooling problem of the W-wave band sheet electron beam. When in work, the tube wall has the maximum temperature of 60 DEG C and meets the requirements of the actual project.

The invention belongs to a coaxial dual-electron beam electron gun matched with a gyrotron (an oscillator and an amplifier), which comprises an electron gun barrel body, a base, a cathode sleeve withan 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 (telescoping) manner, and the control anode is arranged between the internal and external anodes and a cathode head so as to regulate the current of an electron beam and the rotation speed and axial speed of the electron beam in the gyrotron. Therefore, the coaxialdual-electron beam electron gun has the characteristics that the output power can be regulated quickly, the work efficiency of the gyrotron 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 matched with the electron gun are effectively improved, breakdown between the internal and external anodes and the cathode sleeve and between the control anode and the cathode sleeve is prevented, the miniaturization of devices is facilitated, and the like.

The invention provides an over-mode dual-band extended interaction oscillator based on a three-dimensional metal gate, and belongs to the field of vacuum electronic devices. The oscillator is based onthe mode selection characteristic of waveguide loaded three-dimensional metal gates, by designing a specific three-dimensional metal gate structure, the extended interaction oscillator can have the advantages of over-mode and double-frequency work at the same time, the electric large size is achieved in a high-frequency band, the power capacity of a device is increased, and machining and assembling are easy; and due to the centralized interaction in the longitudinal direction, the longitudinal length is shorter, the volume of a focusing magnetic field is reduced, and the overall structure ismore compact.

The invention provides a resonant cavity and a terahertz extended interaction oscillator of a cross structure. The terahertz extended interaction oscillator of the cross structure is greatly differentfrom a traditional terahertz extended interaction oscillator. In a conventional device, a longitudinal electric field is distributed in one direction (such as an x-direction or a y-direction) in a concentrated manner; while a longitudinal electric field is distributed in two directions (i.e., the x-direction and the y-direction) at the same time in the device of the cross structure. Therefore, inthe structure, the energy exchange efficiency of the longitudinal electric field and the cylindrical electron beam can be effectively enhanced, and the output power can be effectively improved. The device can work under the working conditions of 14kV and 0.1 by optimally designing the cross extended interaction oscillator working at 0.3 THz, and the power output of about 51.5 W can be realized. The cross structure is suitable for improving the output power of the terahertz extended interaction oscillator, and is particularly suitable for improving the engineering realizability and the workingstability of a device under lower working current.

An RF cavity is provided with a plurality of tubes that are formed into a tubular cage in a predefined shape to define the RF cavity. A selected number of tubes and a selected tube diameter are provided to form a confinement cage for the RF fields within the RF cavity defined by the tubes. The multiple, small metal tubes are selectively bent to form different cavity shapes and sizes as needed to accelerate the particles and function as a confinement cage for the RF fields within the RF cavity defined by the tubes. The cost to fabricate RF cavities using the tubular cage design is significantly lower than the cost of producing a solid cavity using conventional fabrication technology.

An electron gun. The electron gun includes an RF cavity having a first side with an emitting surface and a second side with a transmitting and emitting section. The gun also includes a mechanism for producing an oscillating force which encompasses the emitting surface and the section so electrons are directed between the emitting surface and the section to contact the emitting surface and generate additional electrons and to contact the section to generate additional electrons or escape the cavity through the section. A method for producing electrons.

A linear accelerator with improved efficiency is disclosed. The linear accelerator contains at least one lower beam energy recirculating linear accelerator which is focused along a constant focal length, and at least one higher beam energy recirculating linear accelerator which is focused along a constant focal length, and a full energy recirculating line which received the beam from the higher energy recirculating linear accelerator and reinjects it into the higher energy recirculating linear accelerator, thereby balancing the focusing profile to the beam energy. Better envelope control, focusing, and higher efficiency is observed in linacs according to the present invention.