Abstract: A cathode body for an impregnated scandate cathode is obtained by compressing and sintering a mixture of tungsten powder with approximately 0.5% by weight of scandium, whereafter the body is impregnated.

Abstract: For maintaining a monolayer of scandium which is necessary for a satisfactory emission on the surface of a scandate cathode, at least the top layer of the cathode is provided with scandium coated with a scandium oxide film. Even after repeated ion bombardment the emission is found to recover up to approximately 90% of the initial value at a current density of ca. 100 A/cm.sup.2.

Abstract: An oxide cathode comprising a base 1 which consists substantially of titanium and a heater element 5 coated with aluminium oxide 6 to heat the base 1, which bears a porous alkaline earth metal oxide emissive layer 4. When the surface of the titanium base 1 which is opposed to the heater element 5 bears a metal layer 7 consisting at least of one of the metals Pt, Mo, Ta and W, a solution is obtained to the problem occurring in titanium cathodes in that titanium in contact with aluminium oxide is not chemically stable. The metal layer preferably consisits of pure tungsten and is formed by chemical vapour desposition (CVD). The metal layer is preferably from 1 to 10 .mu.m thick.

Abstract: A method of producing a dispenser cathode provided with a top layer, in which a main body of tungsten powder is pressed to a moulding at a first pressing pressure which is sufficient to preserve the shape of the moulding when the first pressure is removed but is not sufficient to break the powder grains to a significant extent. This moulding is thereafter provided with a top layer of a second power, whereafter the overall assembly is compressed in a second pressing operation at a second, higher pressing pressure, at which pressure the powder grains are broken to a significant extent.

Abstract: The connector comprises two coupling elements (1) in each of which end parts of light conducting fibres (9) are secured mutually in parallel beside each other in such a manner that the centers of their end faces (15) are situated on one line (17) in an end face (19) of the coupling element (1). The connector further comprises a connector housing (25) for receiving the two coupling elements (1). Each coupling element (1) has a cylindrical outer surface (20) the axis of which coincides with the axis of the light conducting core of one of the fibre end parts (9) secured therein (preferably the central one) and which is capable of cooperating with a centring member (27) of the connector housing (25). Each coupling element furthermore has an orientation element (23) which is capable of cooperating with an orientation member (29) of the connector housing (25).

Abstract: A method of manufacturing a scandate dispenser cathode having a matrix (1) at least the top layer of which consists substantially of a mixture of tungsten with scandium oxide or with a mixed oxide comprising scandium oxide. When sintering of the matrix is carried out at a temperature between 1300.degree. and 1700.degree. C., preferably at approximately 1500.degree. C. and in a hydrogen atmosphere, cathodes are obtained having a better recovery after ion bombardment compared with cathodes sintered at 1900.degree. C. Sintering in hydrogen results in a better reproducibility.

Abstract: A contact for a semiconductor cathode is produced by thermally bonding leads consisting of one of the metals Ag, Au, Cu and one of the metals Ta, Ti, V. Such a contact does not exhibit degradation when the cathode, after mounting in a vacuum tube, is heated several times to approximately 850.degree. C. for cleaning purposes.

Abstract: For thermocompression sealing at least one of the materials to be joined is provided with an oxide skin before or during the sealing operation. The oxide skin can be formed, for example by firing in air. It has been found that the method is particularly advantageous for seals between a CrNi-alloy and, for example a second element which consists of aluminium, for example the seal between an Al entrance window and a CrNi-steel envelope of an X-ray intensifier tube. Notably by addition of an intermediate material, in particular aluminium, seals can thus be realized between many materials.

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 ink-jet printer contains an ink-jet nozzle (1) connected to a pressure chamber (5) which is recessed in a body (7) and is covered with a diaphragm (13, 15) on which a driving element (17) is fitted. The diaphragm contains an outer plate (13) on which the driving element (17) is fitted and an inner plate (15) provided with an oblong opening (19) which extends between the pressure chamber (5) and the ink-feed channel (11). The opening (19) forms a narrow passage with very accurately defined dimensions between the ink-feed channel (11) and the pressure chamber (5).

Abstract: The invention relates to a method of manufacturing a dispenser cathode having a porous tungsten body, in which a metal oxide is provided in the body and the body is impregnated with barium. Good results as regards life and resistance to ion bombardment are obtained if the comparatively cheap oxides of gallium and indium are used.

Abstract: A display window (11) of a display tube is manufactured from a plate (21) having grooves (22), which plate is fused to a plate (20), so that ducts (25) are present in the display window (11). The phosphor screen (14) is provided on the inside of plate (20). The ducts (25) communicate at one end with a common supply duct (26) having an inlet aperture (27) and communicate at the other end with a common exhaust duct (28) having an outlet aperture (29). A coolant is forced through the ducts (25) for cooling the phosphor screen (14).

Abstract: A dispenser cathode body is manufactured from a sintered metallic powder. A large scandium oxide concentration is provided beneath an emissive surface of the body, resulting in increased life, increased current density, and decreased sensitivity to ion bombardment.

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: In an assembly of at least two electrodes which are connected together in an insulating manner, said electrodes are kept at a given distance from each other by at least one member of an electrically insulating material situated between the electrodes which comprises a core which determines the distance between the electrodes and a jacket which directly adheres to the electrode material by heating. The material of the core has a higher melting point than the material of the jacket so that the core during effecting a connection between the jacket and the electrode material maintains its shape.

Abstract: A focusing shadow mask incorporating an electrostatic lens at each mask aperture is produced by creating an electrode comprising a set of parallel conductors on one surface of an insulator sheet and a second electrode on the other surface. The second electrode has apertures defined either by a second set of parallel conductors that are perpendicular to the first set or by a conductive grid that includes conductors parallel to the first set and other conductors perpendicular to the first set. Additional metal can be built up on either electrode to strengthen the combined structure. After formation of both electrodes, the areas of the insulating material are selectively etched away to form apertures for beams to pass through.

Abstract: A vacuum-tight seal is produced between plate-shaped elements one of which is glass, of a gas discharge display device while maintaining such a pressure on the surface of the elements that they are brought in permanent contact with a spacing member which separates them. Furthermore, at least the glass face plate is preferably heated to such a high temperature that a possible elastic deformation of said element resulting from a pressure exerted on the surface thereof is converted into a plastic deformation.

Abstract: In an assembly of at least two electrodes which are connected together in an insulating manner, said electrodes are kept at a given distance from each other by at least one member of an electrically insulating material situated between the electrodes which comprises a core which determines the distance between the electrodes and a jacket which directly adheres to the electrode material by heating. The material of the core has a higher melting point than the material of the jacket so that the core during effecting a connection between the jacket and the electrode material maintains its shape.

Abstract: A method of making a color selection electrode for a color television display tube in which apertured electrodes are placed in contact with metallic coatings on opposite sides of an insulating foil and diffusion bonded thereto by heat and pressure, and thereafter the metallic coatings and insulating material selectively etched to form apertures corresponding to the electrodes therein.

Abstract: A method of producing a low-pressure gas discharge lamp in which a body of a solid material having a thin, structure of filaments permeable to the gas discharge such as glass wool is disposed. Coherence is given to the filaments by compressing them whereafter they are sucked into the lamp envelope. Compressing, knitting together and producing the wire-shaped elements is done in a funnel-shaped space which is connected at its constricted side to the tubular discharge space.