80results about "Transit-tube focussing arrangements" patented technology

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

A multibeam electron tube with several approximately parallel electron beams passing through a body. Among the beams, at least some define an interbeam volume, each beam defining the interbeam volume being subjected to a perturbing azimuthal magnetic field induced by all the other beams. The tube includes an element allowing, in at least one conducting element located in the interbeam volume, flow of a reverse current in the opposite direction to that of the current of the beams, this reverse current generating, in the beams defining the interbeam space, a magnetic correction field whose purpose is to oppose the perturbing magnetic field. Exemplary embodiments of the present invention especially apply to the multibeam klystrons or traveling wave tubes.

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

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

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.

The present invention discloses a system for the administration of a plasma modified field (PMF) to a subject comprising: (a) a non thermal plasma (NTP) emitting source for emitting a plasma beam; (b) a plasma modified field coupling mechanism (PMFCM) comprising a plasma beam dish having at least one opening for the passage of said plasma beam; said plasma beam dish having a first surface and a second opposite surface; and (c) a controller for controlling said PMFCM. In a main aspect of the invention, said first surface of said plasma beam dish is mounted with: (i) at least one coupling element selected from the group consisting of: (1) at least one ferroelectric element for providing said field; (2) at least one ferromagnetic element for providing said field; (3) at least one piezoelectric element for providing said field; and (4) at least one piezomagnetic element for providing said field; and (ii) at least one reflecting element. In a further main aspect, the PMFCM and said controller are configured to adjust any of said at least one coupling and reflecting element in a predetermined manner thereby providing said PMF for inducing a therapeutic or regenerative or beneficial effect on said subject. The present invention further discloses methods and use of the aforementioned system.

The invention provides a time focusing and time collimating method and device of an ultra-short electron beam bunch. The method is characterized in that in a cavity-shaped structure, front electron beams in the electron beam bunch have low acceleration, and back electron beams in the electron beam bunch have high acceleration; after a specific distance, the back electrons in the electron beam bunch catch up with the front electrons in the electron beam bunch, thereby realizing the time compression; and meantime, the electron beam bunch is decelerated, wherein the deceleration of the front electrons is low, and the deceleration of the back electrons is high, so that the movement speeds of the electrons are equivalent, thereby realizing the time collimation. After uneven acceleration, the time width of the electron beam bunch is compressed to 200fs by the invention, and the time compression ratio reaches 3:1.

In a high intensity discharge lamp, at least one of an arc bend amount and an apparent width of arc is controlled by a simple configuration at low cost. A high intensity discharge lamp system 110 has a high intensity discharge lamp 111 and an operating circuit 113 for driving the high intensity discharge lamp 111. In the high intensity discharge lamp 111, a rare gas and a filling material 136 containing a metal halide as a light generating substance are enclosed in the arc tube 121 provided with a pair of electrodes 122a and 122b. The lamp system is disposed such that the line connecting the electrodes 122a and 122b is horizontal, and by applying a magnetic field having a vertical magnetic flux thereto and by varying the frequency of alternating current for driving the high intensity discharge lamp 111, at least one of an arc bend amount and an apparent width of arc can be easily controlled.

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

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.

A switchable ion gun switchable between a cluster mode setting for producing an ion beam substantially comprising ionised gas clusters and an atomic mode setting for producing an ion beam substantially comprising ionised gas atoms, comprising:

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

A plasma ion source includes a plasma chamber body having at least one inlet for introducing a feed gas to an interior of the plasma chamber body. The plasma chamber body is electrically isolated froma vacuum chamber attached to the plasma chamber body. An inductive antenna in an interior of the plasma chamber body is configured to supply a source of electromagnetic energy as a function of an RFvoltage supplied thereto. The plasma ion source includes an extraction grid disposed at an end of the plasma chamber body. A voltage difference between the extraction grid and plasma chamber body accelerates charged species in a plasma discharge to generate an output quasi-neutral plasma ion beam. A bias voltage applied to the plasma chamber body includes a portion of the RF voltage supplied to the antenna combined with a pulsed DC voltage.

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

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.