Abstract: An impregnated cathode comprising a refractory porous body whose pore parts are impregnated with an electron emissive material including barium and a thin film layer comprising tungsten, scandium and/or an oxide of scandium, deposited on the surface of the refractory porous body, characterized in that the thin film layer contains an oxide of tungsten, and/or an oxide of tungsten and scandium, has a distinguished electron emission property and a long life.

Abstract: A reactionless thermionic cathode for electronic tubes consists of a metallic or ceramic support and an alloy, preferably an intermetallic compound, containing the actual emission-promoting element, with a metal from the group comprising those of the VIIIth vertical row of the periodic table and rhenium. The preferred activation substances are platinides of the elements having a low electron work function, predominantly Ba and La. The cathode is manufactured by wet-mechanical, cataphoretic or electroplating application of the activation substance to the support or by infiltration of the porous support having a pore volume of at least 10%. High emission current densities are obtained at relatively low operating temperatures.

Abstract: The invention is directed to a gas discharge lamp particularly to a flash bulb and a method of making the flash bulb. The cathode member is formed by a sintered member whose outer shape is matched to the inside shape of the cavity of the housing in the cathode region and this sintered member is fused in the housing to form the connection with the lead of the cathode.

Abstract: The present invention relates to an impregnated cathode produced by attaching at least two layered thin films, the thin films comprising an under layer consisting of a high melting point metal thin film composed of, for example, Os, Ru, Rh, Pd, Ir, Pt, Re, Mo, W, Ta, etc., and an over layer consisting of a high melting point metal layer which contains Sc.sub.2 O.sub.3 and which is placed over the layer, on the surface of the impregnated cathode pellet generated by impregnating a refractory porous base body with electron emissive materials. The invention relates also to an electron tube having this cathode. This cathode maintains a low work functional mono-layer stably for a long period of time on its surface.

Abstract: In order to improve the stability of a cold cathode (5) of the reverse biased junction type, a vacuum space (2) is coupled with a reservoir (10), within which a source (21) of material reducing the work function, for example caesium, is present. By influencing the vapor pressure and the temperature in component parts (13, 16) of the reservoir (10) and in the source (21), loss of caesium due to adsorption or other phenomena occurring at the emitting surface (8) of the cathode (5) can be compensated for by an incident flow of caesium (25).

Abstract: The efficiency of a semiconductor cathode can be increased by bombarding the electron-emitting regions (8) with an electron beam (8), which frees the surface from adhered oxygen particles. The electron beam preferably originates from a second semiconductor cathode (42), which has an opening (42) for passing the electron beam (20) of the first semiconductor cathode (20). Alternatively, both semiconductor cathodes can be realized in one semiconductor body.

Abstract: An electron-emitting surface is provided with a material reducing the electron work function, which is obtained from a suitable reaction. The reaction mixture or the product to be decomposed, for example CsN.sub.3, is present in a surface depression of a semiconductor body, while one or more pn junctions act as a heating diode. Upon heating, cesium is released and deposited on the electron-emitting surface.

Abstract: A method of manufacturing a cathode for magnetron comprises a cathode sleeve formed as a hollow cylinder, a heater inside the sleeve, two end shields formed around the sleeve at a prescribed interval and an electron emitting material applied around the sleeve between both end-shields, wherein a plurality of isolated projections are almost regularly and intergraly formed around the sleeve between the end-shields, and the above electron emitting material is applied onto the cathode sleeve to fill gaps among the plural projections.According to the method of manufacturing a cathode of the present invention, the efficiency of electron emission and electric conductivity are not lowered, whereby the stable operation can be realized for a long term.

Abstract: The structure is material such as a ceramic in the form of a bundle of open cells, a "honeycomb", with the shape of the cells corresponding to the shape of the openings desired in the grid. The cathode is formed in the cells, rather than adding the grid to a ready-made cathode. The grid is formed by coating the end of the cell walls with a conducting material (metal and/or carbon). The surface of the cathode is suitably recessed from the grid.

Abstract: The cathode and tube of this invention comprise a secondary emission semiconductor cathode in a crossed-field high power amplifier. A gallium arsenide semiconductor doped with an impurity to make it more conductive than intrinsic gallium arsenide has been found to perform better than prior art secondary emission cathodes when it is incorporated as a cathode in a high-power crossed-field amplifier tube operating at high average and peak current. With a gallium arsenide cathode, the crossed-field amplifier tube exhibits a radio frequency output pulse which has fast rise time and much reduced leading-edge jitter relative to performance of the same cross-field amplifier tube having a conventional secondary emission cathode.

Abstract: A thermionic cathode fabricated by cosputtering alkaline earth oxide and al powders under temperature and pressure conditions that ensure a metal particle size in a preferred range.

Abstract: Porous agglomerates are made from pure tungsten by sintering fine particles together and mechanically breaking down the mass to form some agglomerates considerably larger than the particles. These agglomerates are mixed with fine iridium powder and sintered to form a porous mass. The mass is machined to the cathode shapes and impregnated with an alkaline earth aluminate. The large agglomerates alloy with the iridium only on their outer surface. Their pure tungsten interior provides the surfaces to reduce the alkaline earth oxide to the metal which activates the cathode.

Abstract: A gas discharge lamp such as a flashbulb consisting of an anode and a cathode in a transparent housing, the cathode being composed of a sintered member made up of powdered titanium (Ti), and vanadium (V), as well as at least one of the other metals tantalum (Ta) or niobium (Nb), the particles having a grain size of no more than 50 microns, and the Ti being present in a precentage of at least 40% by weight, and the V content being at least 10% by weight.

Abstract: For the reduction of the work function of the electrodes, gas discharge arresters contain an activator which contains, for example, an alkali metal or nickel. Getter materials, for example barium aluminum, serve the purpose of gettering of gases which can arise in the surge voltage arrester during manufacture or during operation. With these substances, the spreads of the minium operating voltage can be maintained small as long as the activator is only moderately heated. For high loads, the activator contains an alkali metal or nickel and, in addition, barium aluminum, whereby tungsten and/or molybdenum is present as the additional substance. An activator of this type guarantees constant values of the minumum operating voltage and a narrow spread of these values even after a high electrical and thermal load. A frequent switching of the maximally permissible current is possible without an interfering alteration of the electrical characteristics.

Abstract: A device is disclosed which produces high current, low noise, low lateral energy, stochastic electron emission from a multiplicity of insulative particles subjected to a field. The insulative particles are in and of a surface thickness comprised of a random mixture of insulative and conductive particles in ohmic contact. Emission is achieved at applied potentials of about 5 volts which produce a field sufficient to emit electron currents of nanoamperes to milliamperes. Single devices or arrays of devices may be batch fabricated. Each device has an imtegral, implicity self-aligned electron optic system comprising means for modulating, focusing and deflecting the formed current beam, and means shielding the device from ambient magnetic fields.

Abstract: The invention is a polycrystalline sintered body based on lanthanum hexaboride and having a density of at least 95% of the theoretical density. The sintered body comprises lanthanum hexaboride, boron carbide and amorphous carbon, the content of B.sub.4 C+C being from 0.1 to 10% by weight and the total amount of La+B+C being at least 99.0% by weight, in each case calculated on the total weight. The sintered bodies have a homogeneous microstructure with mean grain sizes<10 .mu.m, in which, in addition to the crystalline lanthanum hexaboride phase, boron carbide and carbon are detectable as separate, finely divided phases.The sintered bodies can be manufactured by pressureless sintering at temperatures of from 2150.degree. to 2200.degree. C. from powder mixtures comprising lanthanum hexaboride and, in addition, mixtures of a carbon-containing material and a boron component.

Abstract: The invention provides a travelling wave tube having a directly heated cathode. Cathode material is applied in a depression in one U-shaped member of a high resistance alloy material and the return path for heater current is provided by another U-shaped strip member beneath the first. The configurations of the two strip members are similar so that stray magnetic fields generated by the equal but opposite currents flowing therein, tend to neutralize one another. In another embodiment the two strip members are replaced by generally cylindrical members, one member being within the other. The surface of the member providing the return path for heater current is polished where it faces the member carrying the cathode material so as to reflect back heat radiated by the last-mentioned member.

Abstract: A device for picking up or displaying images includes a semiconductor device having at least one cold cathode. The semiconductor device is mounted to the outside of the device for picking up or displaying images by being fixed to a support having an opening to permit the passage of electrons from the semiconductor device to the interior of the devices for picking up or displaying images. This mounting configuration offers the advantages of simple cooling of the semiconductor device, direction connection of the semiconductor device, and improved electro-optical performance.

Abstract: A tuning assembly (42) is disclosed for selectively oscillating the frequency of an electromagnetic field within a hermetically sealed pulsed magnetron (12), comprising a rigid, hermetically sealed housing (14), apparatus for generating the electromagnetic field therewithin (32, 34, and 36), and elements for defining a cavity (30) within the housing for establishing the frequency of the electromagnetic field. The tuning assembly (42) includes electrically conductive members (54) mounted for linear movement within the cavity (30) to oscillate the established frequency. Elements (52) disposed within the rigid housing (14) are provided for mounting the electrically conductive members (54), and are adapted for oscillatory movement at a predetermined mechanical resonant frequency to move the electrically conductive members (54) linearly.

Abstract: In a directly heated cathode including a base formed of an alloy containing nickel as its principal component and coated with an oxide of an alkaline earth metal which emits electrons, a layer of a metal selected from the group consisting of nickel, cobalt, platinum and rhodium or of an alloy containing one of these metals as its principal component is formed on both surfaces of the base to one of which surfaces the coating of the oxide is applied, so as to thereby prevent the peeling-off of the coating of the oxide from the base. In order to avoid deformation of the base, a powder alloy containing tungsten and nickel as its principal components, a powder alloy containing molybdenum and nickel as its principal components or one of these powder alloys which is coated with nickel, cobalt or a cobalt-nickel alloy is deposited on the surface of the base to which the coating of the oxide is applied.

Abstract: A long life high current density hollow cathode electron beam source for use in various E-beam apparatus which uses an ionizable gas within the hollow cathode. Bombardment of an electron emissive surface within the hollow cathode by energetic gas ions causes electrons to be emitted by secondary emission rather than thermionic emission effects. Once initialized by an external ionization voltage the device is essentially self sustaining and operates near room temperature, rather than at thermionic emission temperatures, and with reduced voltages.

Abstract: High pressure sodium lamps have been subject to progressive reduction in pressure of contained sodium with attendant reduction in lighting quality. It has been discovered that modification of lamp components permits the pressure of contained sodium to be maintained at higher levels. Emission materials enclosed within the lamp are altered to limit reactive oxygen in the lamp atmosphere. A thermionic electrode as equipped with an improved emission composition as illustrated in areas B and C of the triaxial plot of FIG. 3.

Abstract: Method of fabricating an cold cathode for a laser such as ring laser gyro characterized by the use of vitreous carbon as the material of the cathode. For this purpose a predetermined amount of resin is pressed formed into the shape of a hollowed cathode body which is then heated in an oxygen free environment form a vitreous shaped cathode by thermal degradation of the resinous body. The vitreous carbon material reduces the difference between the coefficients of thermal expansion of the housing and electrode which can cause the indium seal to fail, e.g., in the case of prior aluminum cathode. The electrical connection may be made via either a silver epoxy or indium solder.

Abstract: A method of manufacturing a scandate dispenser cathode having a matrix at least the top layer of which at the surface consists substantially of tungsten (W) and scandium oxide (Sc.sub.2 O.sub.3) and with emitter material in or below said matrix. If said method comprises the following steps:(a) compressing a porous plug of tungsten powder(b) heating said plug in a non-reactive atmosphere and in contact with scandium to above the melting temperature of scandium,(c) cooling the plug in a hydrogen (H.sub.2) atmosphere(d) pulverizing the plug to fragments(e) heating said fragments to approximately 800.degree. C. and firing them at this temperature for a few to a few tens of minutes in a hydrogen atmosphere and slowly cooling in said hydrogen atmosphere(f) grinding the fragments to scandium hydride-tungsten powder (ScH.sub.2 /W)(g) compressing a matrix or a top layer on a matrix of pure tungsten from said ScH.sub.

Abstract: An electron gun for high brightness including a LaB.sub.6 single crystal cathode having a (100) plane on at least part of a main electron beam emission surface of a cathode tip having a top and a Wehnelt having a tapered surface defining an interior angle similar to or greater than a vertical angle of said cathode tip.

Abstract: An emitter-dispenser housing for a controlled porosity dispenser cathode manufactured of a single material as a unitary piece by a chemical vapor deposition process in which a configured mandrel is coated with a layer of material such as tungsten, for example, so that when the mandrel is removed from the coating of material a hollow housing is formed having a side wall and an end wall which define a reservoir. In addition, intersecting strips of this same material as the coating, which had been placed in the mandrel, extend transversely across the reservoir with the edges thereof atomically bonded to the coating during the chemical vapor deposition to form a unitary piece. Thereafter an array of apertures is formed in the end wall of the housing by laser drilling to create an emitter-dispenser.

Abstract: A preferably fully impregnated dispenser cathode member or the like forming part of an electron tube, electron beam generator or the like is initially heated by any suitable means to a temperature sufficient for low level electron emission from its rear surface. A hot plate member of preferably equal size is disposed behind the cathode and can either be part of or the means for initially heating the cathode member or it can be heated with the cathode member to the aforementioned cathode member's rear surface low level emission temperature. A sustainer voltage is applied between the cathode member and the hot plate member sufficient to draw a current comprising electron flow from the cathode member to the hot plate member across the space separating them.

Abstract: The invention provides a direct heating thermo-electronic emission cathode comprising a pyrolytic graphite support and an emissive coating formed of a mixture of tungsten and lanthanum oxide, the tungsten being transformed in its surface part into tungsten hermicarbide.

Abstract: A thermionic cathode (FIG. 1) comprises an emitter (3) comprising a matrix (4) of tungsten impregnated with an alkaline earth activator. The matrix is coated with a coating (5) of about 20-30% osmium fully alloyed with tungsten formed by cosputtering osmium and tungsten onto the matrix. A diffusion barrier (6) of osmium may be interposed between the matrix 4 and coating (5) (FIG. 2) and, optionally, osmium may be diffused into the matrix (4). Alternatively the whole matrix may comprise a mixture of about 20-30% osmium fully alloyed with tungsten (FIG. 3). Alternative to osmium and tungsten may be used, and various modifications may be made, and other methods of making the emitter may be used. In particular the proportion of osmium may be about 40%.

Abstract: Directly heated oxide cathode especially for velocity-modulated tubes in pulse operation, characterized by the features that an outer conductor is designed cylindrically and an inner conductor is coaxially arranged by means of a ceramic support disc, and that on one end face, a metal layer connected to the outer conductor and the inner conductor is provided with an electron-emitting oxide layer.

Abstract: A DC gas discharge display panel is described, having a cathode which is formed by depositing a metal and/or a metal compound on a substrate of the DC gas discharge display panel or a cathode substrate by the application of plasma spray utilizing plasma generated by the discharge of a rare gas, or a mixed gas of a rare gas and hydrogen and/or nitrogen.

Abstract: A cathode for a cathodoluminescent display device includes a plurality of low coefficient of expansion support columns arranged in a substantially parallel spaced relationship, a resistive cathode heater member extends between and is permanently affixed to the support columns. An electron emissive coating is on a portion of the cathode heater member between the columns.

Abstract: Disclosed is a method and apparatus for producing a high electron beam current having a low energy spread at a high brightness of the beam and a uniform intensity distribution. The electron beam is extracted from an emission current which consists of used emission current and unused emission current. The used emission current has a uniform intensity distribution. The apparatus produces a negligibly small unused emission current by using both a frustum shaped cathode and a multi-electrode. The cathode comprises a thermoelectron emissive material having a low work function and one or more thin layers which cover the side surface of the cathode. A material of the outermost thin layer has a high work function. The multi-electrode consists of the cathode, a first grid electrode, a second grid electrode and an anode electrode. The used emission current is generated from the top surface of the cathode. The unused emission current that is generated from the side surface of the cathode is negligibly small.

Abstract: A thickened part (1) of a high-melting metal, which may contain emitter material, is formed on a carrier (2) of a high-melting metal. In order to manufacture such electrode structures in mass production and to obtain both various material transitions and combinations and optimum designs, the thickened part (1) is formed by reactive deposition from the gaseous phase (CVD method), preferably by laser-supported deposition from the gaseous phase.

Abstract: A cathode having a layer structure in which alternate layers consisting essentially of emitter material (2) and base material (1) are provided at an oblique angle to the cathodes's macroscopic emitting surface. In a preferred embodiment the surface has a microscopically stepped structure formed by ends of the base material layers and portions of the emitter material layers coating the ends. In an alternative embodiment the surface is not stepped but is formed by a polycrystalline or a preferentially oriented polycrystalline coating layer which is provided on the succession of beveled layers. The succession of layers is manufactured by alternating depositions from the gaseous phase and by subsequent bevel grinding of the layers. The polycrystalline coating layer is provided by deposition from the gaseous phase. The stepped surface is formed, for example, by selective structure etching after the bevel grind.

Abstract: An impregnated cathode comprises a porous refractory substrate of refractory material such as tungsten containing at least one of scandium oxide particles and oxide particles containing scandium such as (Al, Sc).sub.2 O.sub.3, and an electron emissive material impregnated into pores of the substrate, and has an operating temperature lower by about 300.degree. C. than that of the conventional impregnated cathode containing no scandium oxide particles, or scandium.

Abstract: A method of forming a variable sensitivity transmission mode negative eleon affinity (NEA) photocathode in which the sensitivity of the photocathode to white or monochromatic light can be varied by varying the backsurface recombination velocity of the photoemitting material with an electric field. The basic structure of the photocathode is comprised of a Group III-V element photoemitter on a larger bandgap Group III-V element window substrate.

Abstract: This invention concerns a thermoelectronic cathode for hyperfrequency electron tubes.The cathode comprises a cylindrical molybdenum casing, the lower portion of which contains a heating filament, while the upper portion contains two superimposed porous bodies, the lower one made from impregnated material, and the upper one from non-impregnated material.

Abstract: A gas filled surge arrester which has an extremely fast response to rapidly increasing surge voltages. A pair of electrodes define a discharge gap which is held in the range of 0.02 mm to 0.25 mm. A high electron emission ability substance partially fills a cavity in each electrode. At least a pair of conductors are associated with each electrode. The conductors define a discharge gap with the opposite electrode. The gap is held in the range of 0.02 mm to 0.30 mm. A gas made up of one or more of the noble gases and hydrogen fills the arrester. The hydrogen is held in the range of 0.1% to 20% of the total volume of the gas in the arrester.

Abstract: I have discovered that an electron beam emitted from an LaB.sub.6 single crystal cathode has higher brightness when a significant portion of the actual emitting surface of the LaB.sub.6 crystal comprises flat surfaces oblique to the electron beam axis and when these flat surfaces expose relatively low work function crystal planes. I have defined as a relatively low work function crystal plane those crystal planes having a lower work function than the average work function for sintered LaB.sub.6. My preferred geometry for a single crystal LaB.sub.6 electron emitting tip is a pyramid oriented such that the apex points in the electron beam emission direction and preferably also points in a direction perpendicular to a relatively low work function crystal plane. The pyramidal tip may have three, four, or more flat sides, all of which contribute electrons to the beam, from at least an area in the vicinity of the apex. The apex of the pyramid may be rounded or flat.

Abstract: A thermionic emission cathode of a single crystal made of the calcium hexaboride type crystaline structure comprises a top surrounded by natural face inherent to the axial direction of the single crystal.

Abstract: A thermionic emission cathode comprises a cathode tip made of an alkaline earth metal or rare earth metal hexaboride, a metallic support for supporting a base of said cathode tip and a reaction barrier layer comprising colloidal carbon and a reaction barrier material which bonds said cathode tip and said metallic support in one body.

Abstract: Sintering aids are disclosed which improve the sintering of emission materials in high pressure discharge lamps. The sintering aid is Nb.sub.2 O.sub.5 or Ta.sub.2 O.sub.5 or a mixture thereof along with an alkaline earth oxide with is mixed in the amount of 2 to 15 weight percent sintering aid with 98 to 85 weight percent electron emissive material.

Abstract: Depression cathode structures for cathode ray tubes are produced by dispensing liquid cathode material into the depression of a metallic supporting substrate, removing excess cathode material by passing a doctor blade across the substrate surface and over the depression, and drying the cathode layer to a substantially immobile state. The cathode layer may optionally be further shaped prior to substantially complete drying thereof.

Abstract: An oxide cathode comprising a metal base substantially consisting of titanium and a heating element for heating said base, on which base a porous layer comprising an alkaline earth metal oxide is provided. The cathode has a comparatively low operating temperature, a short warm up time and a low power requirement.

Abstract: The shape of an electron beam emitted from an LaB.sub.6 single crystal cathode can be controlled directly by shaping the cathode tip itself. The LaB.sub.6 cathode is provided with a flat top surface which is substantially perpendicular to the emitted beam direction and which corresponds in shape to the shape of the beam desired. For a square beam the flat top surface is square in shape. The size of the shaped top surface and operating conditions are arranged such that emission of electrons occurs over substantially the entire shaped top surface with minimum emission from side regions of the tip adjacent to this shaped surface. In order to maximize emission from the shaped top surface, a crystallographic orientation is selected such that the shaped top surface exposes a relatively low work function crystal plane. Emission from side regions of the tip adjacent to the shaped high emission surface may be reduced by orienting such side regions very obliquely to the emitted beam axis.

Abstract: Cathode structures for cathode ray tubes are produced by dispensing slurry drops of cathode material onto metallic supporting substrates, and drying the drops to form cathode layers. The slurry comprises the particles in an organic binder solution, and additionally contains particles of urea. The cathode layers are subjected to further thermal processing during their incorporation into a cathode ray tube, and are characterized by a high degree of adherence to their underlying substrates.

Abstract: A directly heated type oxide cathode comprising a base made of an alloy containing Ni as a major component and Zr as a reducing agent, a coating of Co powders or a mixture of Ni powders and Co powders wherein the average particle size of the Co powders is smaller than that of Ni powders formed on the base, and an electron emissive alkaline earth oxide layer formed on the coating of Co powders or the mixture of Ni powders and Co powders does not show deformation of the base or peeling of the oxide layer during the production procedure or operation of electron tubes and the like.

Abstract: A tungsten double coil covered with cathode material made from a paste of carbonate mixed with organic solvent. The coil is mounted around a molybdenum cylinder having a cavity in which a heater is installed.

Abstract: A thermionic cathode is disclosed employing an alkaline earth metal hydroxy oxy carbonate as an emission material. Cathodes in accordance with the present invention are capable of operating in the range of 650.degree. C. to 800.degree. C. and can be formed by compressing a powdered mixture of the emission material and a metal.