Abstract: An electron gun for the cathode-ray tube is disclosed, in which an early stage lens unit and a main lens unit are respectively constructed as a bipotential form lens. A high voltage equivalent to the voltage applied to a grid of the main lens unit is applied to a grid of the early stage lens unit thereby to reduce the space charge effect, while at the same time suppressing the change of the beam spot shape with the change in the beam current.

Abstract: This invention relates to an indirectly-heated cathode heater structure comprising a heat generation section disposed inwardly of an upper portion of a sleeve for generating heat to emit thermions at an electron gun of a cathode ray tube, the heat generation section having a given calorific value being formed to have a length 25.about.33 % of the length of the sleeve, whereby heat loss at a lower portion of the sleeve during heating operation of the heater may be minimized, resulting in improving an overshoot rate of the heater.

Abstract: By providing a semiconductor device such as a cold cathode (7) with extra zener or avalanche structure (26, 27 and 32, 33, respectively) a robust structure is obtained which is resistant damage from, e.g., flashoners, during manufacture and use in a vacuum tube. The semiconductor zones (24, 27, 32, 33) are also utilized as electron sources.

Abstract: In a cathode assembly of a cathode ray tube, a cathode having an emitter is inserted in a through-hole formed in an insulator. The emitter is provided so as to face a cylindrical electrode of a first grid at a predetermined distance. A hole communicating with the through-hole is formed at a longitudinal side of the insulator, and a tubularly rising shelter is provided between the emitter in the through-hole of the insulator and the hole. This satisfies (E.times.B)-(C.times.E)+(C.times.D)-(A.times.D).gtoreq.A. D, where the height of the hole is A, the height of the shelter is B, the length from the lower end of the shelter to the head of the cathode is C, the length between the cathode and the shelter is D, and the length between the cathode and the insulator is E. The cathode assembly prevents metal vapor, such as barium oxide of the cathode and nickel or chromium of the sleeve, from spreading through the hole of the insulator.

Abstract: A cathode sheath for a thermionic electron-gun cathode. The sheath is substantially in the form of a hollow cylinder and has an outer surface and an inner surface, a central axis, a closed end and an axially-opposite open end, and a side wall extending between the closed end and the open end. The sheath is a continuous bimetallic laminate having a first layer of material forming the inner surface and a second layer of electron-emission (donor) material overlying substantially the entirety of the first layer and forming the outer surface. The laminate has a preselected thickness at the closed end and has a thickness at the side wall which varies along the central axis. The outer surface of the bimetallic laminate is substantially unreactive with oxygen whereas the inner surface is more readily reactive with oxygen.

Abstract: A compact, high power electron gun having enhanced thermal and mechanical stability which incorporates a mechanically coupled, self aligning structure for the anode and cathode. The enhanced stability, and reduced need for realignment of the cathode to the anode and downstream optics during operation are achieved by use of a common support structure for the cathode and anode which requires no adjustment screws or spacers. The electron gun of the present invention also incorporates a modular design for the cathode, in which the electron emitter, its support structure, and the hardware required to attach the emitter assembly to the rest of the gun are a single element. This modular design makes replacement of the emitter simpler and requires no realignment after a new emitter has been installed. Compactness and a reduction in the possibility of high voltage breakdown are achieved by shielding the "triple point" where the electrode, insulator, and vacuum meet.

Abstract: This invention provides a method of positioning and assembling in place cathode heaters of an electron gun for a cathode-ray tube, thereby resulting in improvements in assembling workability and in the white balance characteristic on the screen of the tube. A cathode heater structure includes a cathode heater and a heater supporter. The cathode heater includes a heat generating portion and a pair of leg portions extending from the heat generating portion. Each leg portion is formed with a bent engaging portion at its end. The heater supporter has guide grooves for receiving the engaging portions of the cathode heater to guide and position them. According to the method of the present invention, the cathode heaters are shot in sequence into the guide grooves of the heater supporter by means of shooters, and then the leg portions of the heaters caught and positioned in the guide grooves are welded to the guide grooves.

Abstract: A majority carrier, solid state cathode uses ballistic behavior to provide a highly coherent (and modulated) electron beam, with a large current density and expected efficiencies greater than fifty percent.

Abstract: A cathode heater includes a patterned conductor embedded within a dielectric substrate. The ceramic substrate has a pair of conductors over the respective surfaces thereof to provide electrical contact for the heater. To assemble the substrates having the conductors, the substrates and printed conductive patterns are fired to provide a composite multi-layer ceramic heater which can be used to heat cathode electrodes in microwave tubes such as travelling wave tubes.

Abstract: Disclosed is a cathode assembly of an electron gun for a color cathode ray tube in which a heater support structure is improved. The cathode assembly of an electron gun for a color cathode ray tube comprising three cylindrical sleeves which are arranged in an in-line type, a base metal which is located at the upper end of the sleeves, and of which the surfaces are coated with thermal electron emitting material, a heater which is located on the inner portion of each of the sleeves and having two parallel terminals which are exposed out of the sleeves, and a heater fixture block in which three pairs of welding terminals corresponding to the three heaters and two signal lines for forming an electrical circuit along with the welding terminals are provided in the lateral surface and two parallel bead glasses for supporting the sleeves and the block. The heater support structure is simple and the stability thereof is improved. Also, the heater is easily assembled to have a high productivity.

Abstract: A planar electron-optical lens is obtained on a semiconductor cathode surface by providing an extra electrode (16) around the gate electrode (14). Dependent on the applied voltage, this configuration operates, for example, as a positive lens which supplies parallel beams without dispersion, suitable for thin, flat display devices. A large positioning tolerance is obtained due to the inherent magnification of the beam diameter in the semiconductor device, while a grid can be dispensed with.

Abstract: An improved cathode structure in an electron gun for a cathode ray tube comprises a sleeve having a cylindrical shape, a heater disposed in the interior of the sleeve, a cap disposed at the upper portion of the sleeve, and an electron-emitting material layer coated on the outer top surface of the cap. A gap having a dimension that is 13.5% to 15.5% of the inner diameter of the sleeve, is defined between the sleeve and the heater, thereby improving an overshoot in emission of electrons at an initial operation state of heater.

Abstract: An impregnated pallet including a porous metal body to which an electron radiating material is impregnated, a cathode ring having an upper portion in which the impregnated pallet is fitted, and a cathode sleeve containing a heater therein and having a closed upper end mounted to the lower end of the cathode ring such that the closed upper end surface thereof is in close contact with the lower surface of the impregnated pallet, so as to transmit directly the heat from the heater accumulated in the cathode sleeve to the impregnated pallet. A plurality of uniformly spaced metal ribbons are formed integrally with the lower end of the cathode ring. Each metal ribbon has an end fixed to the closed upper end surface of a cathode holder. In accordance with the present invention, the impregnated cathode has an improved construction capable of shortening the video producing time and simplifying the manufacturing process, thereby improving the workability and the productivity.

Abstract: A cathode structure for a cathode-ray tube includes a cathode cap coated with an electron-emissive substance for emitting electrons when heated, a cylindrical cathode sleeve attached to the bottom of the cathode cap, a heater inserted in the cathode sleeve for heating the cathode cap, a cathode sleeve holder for holding the cathode sleeve , cylindrical member for fixing the lower end of the cathode sleeve preventing electric field concentration, and a plurality of connecting arms extending from the means for connecting with the cathode sleeve holder.

Abstract: The present invention relates to a cathode support structure of an electron gun for a cathode ray tube for improving the electron beam emission characteristics by way of ensuring the support operation of the cathode, whereby upgrading the white balance holding characteristics and preventing the degradation of carbonate. A cathode support structure of an electron gun for a cathode ray tube which is designed to support the cathode support member 2, 2' or 2" using the support strip 3, 3' or 3" between the bead glasses 1 where the support strip 3, 3' or 3" has semicircular curved surface 3a, 3a' or 3a" which encompassing the cylindrical cathode support meber 2, 2' or 2" for secure fixation and having a pair of integral reinforcement strips 4, 4' or 4".

Abstract: A cathode structure for an electron tube that includes a cathode sleeve, an upper heat radiation part blackened by the oxidation of the Cr contained therein in order to increase the rate of the heat radiation, a lower supporting part covered by a nickel layer for preventing the oxidation of Cr, and a cathode sleeve holder that is connected to the lower supporting part by resistance welding.

Abstract: A potted heater assembly and a method of forming such a potted heater assembly comprises the steps of introducing into a mold having a filament disposed therein a slurry containing a liquid vehicle and particles of a refractory ceramic, said particles having a cylindrical shape and a diameter of generally less than a micron. The method further includes the step of removing the liquid vehicle from the slurry to leave behind a consolidated ceramic embedding the filament, and heating the ceramic having the embedded filament to further consolidate the ceramic to provide said ceramic having a density of at least 85% of theoretical density for the particular ceramic. The potted heating assembly having a ceramic potting embedding a filament heater is provided having higher post-sinter density than prior assemblies and has substantially higher strength.

Abstract: An electron emitting device is provided with a p-semiconductor layer formed on a semiconductor substrate. The p-semiconductor layer is composed of a diamond layer.

Abstract: A direct heating cathode structure for a miniature cathode ray tube is disclosed wherein angular rod-shaped supports where the coiled heater is welded are bent so that one edge thereof is directed upward, and opposing delta welding portions are formed by chamfering the top edge of the bent front part of the supports, thereby allowing simple ascertainment of the proper welding location and rapid precision welding of the coiled heater.

Abstract: The present invention provides an electron beam gun for an electron beam evaporation source in which a beam former shields a filament from an anode such that electrons emitted from the filament are accelerated past the anode in a ribbon-like beam. The filament is connected to a split cathode block having two sides for applying an electric current through the filament. The beam former has two sections which are separately connected to the two sides of the cathode block such that the cathode block acts as a heat sink for the beam former, and a thermal gradient is not produced within the beam former that would produce warpage and movement of the beam former. Preferably, the vertical gap is about 0.254 mm. to prevent electrons emitted from the filament from arcing through the gap to the anode.

Abstract: The present invention involves a cathode structure for an electron tube wherein the cathode sleeve and cathode sleeve holder are fixed together by improved means so as to increase the exposed length of the cathode sleeve that has a cathode heater, a cathode holder for holding the cathode heater, a cathode sleeve with an upper end and lower end for enclosing the cathode heater, the upper end sealed by a cathode cap, a cathode sleeve holder with an upper end and lower end for holding the lower end of the cathode sleeve and the cathode holder, an outward flange formed around the lower end of the cathode sleeve, and an inward flange from around the upper end of the cathode sleeve holder, wherein in the outward flange of the cathode sleeve is caught by and bonded to the inner flange of the cathode sleeve holder.

Abstract: A cascaded magnetron device has an elongate cathode shank extending along its axis and a series of tubular anode elements placed end to end in a linear cascade surrounding the cathode shank along at least part of its length. Each adjacent pair of anode elements is separated by a conductive, annular pin down disc, and the cathode shank has a series of spaced bands of field emitting material separated by non-emitting regions, each band being located within a respective one of the anode elements and spaced inwardly from the ends of that element. Suitable power inputs and magnetic field generators are provided for generating electron emission and oscillation in the interaction zone between each emitting band and the anode element surrounding that band, and suitable extraction devices are provided for extracting power from each of the interaction zones, the arrangement producing phase-locking of the cascaded magnetron bodies.

Abstract: A relativistic magnetron device comprising an elongate cathode shank extending along the axis of the device and a cylindrical anode surrounding the cathode shank along at least part of its length to define an annular interaction area. The anode has an even number of resonator cavities facing the cathode, and microwave extraction devices are connected to alternate resonator cavities to extract power from the device. The cathode has a central, emission band extending from the center of the interaction area in opposite directions and terminating short of the ends of the anode, while the remainder of the cathode is non-emitting.

Abstract: A display device having a row of emitting elements and an electron-optical system for the electron beams emitted by the said elements. The electron-optical system includes bodies to which common row electrodes are secured so that the assembly of the electron-optical system is simplified. The electrodes may be provided either as separate elements fitting into slots in the body walls, or as layers on the walls, formed for example by vacuum evaporation.

Abstract: The present invention relates to an inorganically insulated heater having a long life for use in air flow sensors, cathode ray tube cathode heaters etc., wherein the distribution of inorganic insulating particles of the whole insulating layer is made uniform and thereby the development of cracks and the like in the insulating layer is reduced and breaking of wire and dielectric breakdown occur with difficulty even at high temperatures and under strong vibrations.

Abstract: A microwave electron gun for a linear accelerator uses microwave energy to impart an initial acceleration to electrons emitted from a lanthanum-hexaboride cathode. The microwave are contained in an electron-gun cavity, the upstream wall of which has a protruding part surrounding the entrance opening that accommodates the cathode, and the downstreams wall of which has a flat part surrounding an exit opening. The rest of the downstream wall has a radius of curvature equal to that of the other microwave cavities in the accelerating tube, and its center of curvature is aligned with theirs. The cathode is fused to a pair of carbon electrodes to form a cathode block, which is held by clamping between a pair of electrode bars, thus forming a cathode tube. The cathode tube is inserted into a sleeve upstream of the entrance opening in the electron-gun cavity, and is surrounded at a distance of one quarter-wavelength from the cathode by a disk-shaped choke cavity extending one quarter-wavelength from the cathode tube.

Abstract: Three pipes for supporting three cathodes of an electron gun for an in-line type color cathode-ray tube parallel with one another in one and the same plane are arranged in one and the same plane, peripheral portions of the pipes are surrounded by a laterally extending cylindrical outer supporting frame extended in an arranging direction of the pipes through a fixing agent formed of crystallized hard glass powder with low melting point to fix the pipes, and a trapizoidal notch is provided upwardly of a lower side of the cylindrical outer supporting frame and along axes of the pipes to thereby prevent the pipes from being deformed.

Abstract: A RF electron gun, such as for use in a linear electron accelerator, having a cathode activating device which, in one embodiment, includes means for altering the phase of the accelerating electric field to accelerate emitted electrons in the reverse direction to cause them to strike the cathode, thereby activating the cathode. In another embodiment, laser light is directed onto the cathode for activation thereof and, in a further embodiment, the electric field is positioned and directed at the cathode to cause the activation thereof.

Abstract: A solid-state electron beam generator has a hetero bipolar structure comprising an emitter region having a first band gap, a base region having a second band gap narrower than the first band gap, and a collector region having an electron-emitting surface. Electrons are injected from the emitter region into the base region while a backward bias voltage being applied between the base region and the collector region. In consequence, electrons are emitted from the electron-emitting surface of the collector region. The emitter region is constituted by an N-type Al.sub.x Ga.sub.1-x) As layer (0<x.ltoreq.1) having the first band gap and formed on an n-type or n.sup.+ -type GaAs substrate or a semi-insulating GaAs substrate, the base region is constituted by a P-type Al.sub.z Ga.sub.(1-z) As layer (0.ltoreq.z<x) having the second band gap, and the collector region is constituted by an n-type Al.sub.t Ga.sub.(1-t) As layer (0.ltoreq.t.ltoreq.1) formed on the n-type or n.sup.

Abstract: An indirectly heated type cathode assembly comprises a cathode sleeve having a heater within itself and having an emitter-impregnated type cathode disc fitted at one end, a plurality of straps connected at one end to a lower end portion of the cathode sleeve, and a cylinder holder whose upper end is connected to the other end of each strap, the holder being located outside the cathode sleeve such that it is spaced a predetermined distance apart from the cathode sleeve. A heat reflecting cylinder is located between the cathode sleeve and the holder of the indirectly heated type cathode assembly such that it is coaxial with the cathode sleeve and holder. The heat reflecting cylinder is supported by the holder and each strap extends such that it is not in contact with the heat reflecting cylinder. The strap is made of a Ta-W alloy or a Ta-W-Hf alloy.

Abstract: An electron gun heater supporting structure includes a pair of supporting pieces respectively mounted on separate opposed glass beads of an electron gun and U-shaped connecting pieces disposed between the pair of supporting pieces for welding terminals of a heater thereto, the connecting pieces including position determining elements for determining the positions of the connecting pieces relative to the supporting pieces for welding them together. According to the present invention, the welding positions can be exactly determined and the uniformity of heater positions can be realized.

Abstract: This cathode has a body made of a material that does not emit electrons, having a substantially smooth non-emissive face and elements made of an emissive material each having an emissive face, spaced out from one another and fixed to the body, for example in hollows with their emissive surface in relief by a determined value with respect to said non-emissive face, so that a protection electrode can be placed between the projecting parts of these elements.

Abstract: An electron gun cathode and a manufacturing method therefor includes a unitary cylindrical sleeve having a bottom with through-holes for the passage of the terminals of a heater. The heater is disposed in a closed space formed by the sleeve and a base joined to the sleeve opposite its bottom. The heater is sealed in the closed space of the sleeve and base to promote thermal efficiency, reduce heat loss between the base and the sleeve, and reduce power consumption of the cathode.

Abstract: The invention relates to an electron gun comprising a cathode-unit composed of a cathode shaft (53) which is surrounded by a heat reflection screen (56). A connection piece (55) is secured to the head end of the cathode shaft (53). A holder (59) containing electron-emitting material (60) is located on the connection piece (55). The cathode shaft (53) is suspended in the heat reflection screen (56) by means of suspension wires (57), each wire being secured to the heat reflection screen with one end which is at least close to the head end of the heat reflection screen (56), and the other end (58) being located between the connection piece (55) and the holder (59).

Abstract: A dispenser cathode body includes a heat capturing portion extending rearwardly from the dispenser cathode, said heat capturing portion having greater mass and thickness than an exterior support skirt. A slip-in heater is received within the heat capturing portion. Substantially greater electron emission density is secured without requiring injuriously high temperatures from the slip-in heater.

Abstract: An electron gun assembly for use in a color CRT includes a pair of insulating support rods, three inline indirectly heated cathode disposed between the support rods, a heater for each of the cathodes and a pair of improved, reinforced heater tabs. The heater includes a pair of heater legs which are attached to the heater tabs. Heater bead straps are provided for attaching the heater tabs to the support rods. The electron gun also includes a plurality of electrodes for focusing and accelerating an electron beam generated by the cathodes. The reinforced heater tabs comprise a main body portion including a first and a second part. Each of the parts is attached to one of the heater legs. Each of the heater tabs has a pair of outwardly directed feet each of which is connected to one of the parts of the main body portion by a pair of substantially orthogonal legs extending therebetween.

Abstract: In an electron tube sealing structure, a cylindrical insulator is metallized to produce metallized layers on both end surfaces, and sealing metal members are soldered to the metallized layers correspondingly, so that a vacuum chamber is provided in the interior of the cylindrical insulator. The cylindrical insulator is provided with at least one salient portion at an inner end thereof. The salient portion is parallel to a direction of an electric field produced by a voltage applied across the sealing metal members, and shields one of the metallized layers which is positioned on the side of a negative electrode in regard to the vacuum chamber, so that the emission of electrons is avoided from the corresponding metallized layer to prevent a creeping discharge from being induced on the inner surface of the cylindrical insulator.

Abstract: The stability of semiconductor cathodes is improved by reducing the effective emitting surface area. This is effected by producing emission patterns by means of separate emission regions, whose overall surface area is much smaller than that of the actual emission patter. Due to the higher emission current and adjustment current, adsorbed particles, which adversely affect the stability of the emission, are rapidly drained.

Abstract: Apparatus for forming an electron beam sheet includes a cathode member having a slot in a front surface thereof, a grid electrode and the anode of a thyratron. When it is desired to trigger the thyratron into conduction, a suitably large potential difference is applied between the cathode member and the grid, resulting in an electron beam sheet being produced extensive of a slot formed in the front surface of the cathode member. This produces ionisation and a main discharge current is established between the main anode and cathode of the thyratron.

Abstract: An electron emission device for attracting electrons emitted from an electron emission element to an anode, includes a current detector for detecting a flow-in current to said electron emission element and a flow-out current from the electron emission element. The difference between the flow-in current and the flow-out current is calculated and the voltage applied to the electron emission element is adjusted in accordance with the difference between the flow-in current and the flow-out cuttent.

Abstract: An electron gun assembly for use in a CRT includes a pair of insulating support rods, at least one indirectly heated cathode disposed between the support rods, a heater for the cathode and an improved heater tab. The heater includes a pair of heater legs which are attached to the heater tab. Heater bead straps are provided for attaching the heater tab to the support rods. The electron gun also includes a plurality of electrodes for focusing and accelerating an electron beam generated by the cathode. The improved heater tab comprises a main body portion including a first and a second part. Each of the parts is attached to one of the heater legs. The heater tab has a pair of outwardly directed feet each of which is connected to one of the parts of the main body portion by a pair of substantially orthogonal legs extending therebetween.

Abstract: A crossed-field amplifier has a cathode in the form of a P-N junction semiconductor which is biased to the conductive state to cause the crossed-field amplifier to amplify. The P and N regions of the semiconductor are connected to an energy source which is pulsed to produce conduction in the P-N junction and thereby allow secondary emission from the cathode. A reverse bias voltage prevents secondary emission from the cathode. The tube requires only low voltages to be applied to the cathode P-N junction to completely deactivate the crossed-field amplifier tube without requiring the removal of the RF drive pulse applied to the cathode- or anode-slow-wave circuit and without requiring the removal of the DC high voltage power supply which therefore need not be pulsed.

Abstract: Positive ions generated in a vacuum tube (1) which may detrimentally influence the electron emission of a cathode (3) are trapped by a plate (35). The plate is present in an aperture (36) in a grid (37) to which it is connected via bars (40). The aperture (36) is sufficiently large to pass the generated beam (6), while the bars (40) hardly influence the beam intensity.

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: A color picture tube comprises electron guns disposed in the corners of a triangle, a slit-type shadow mask and a phosphor screen consisting of vertical phosphor stripes. In the electron-gun system and/or on the side thereof facing the deflection unit, or between the electron-gun system and the deflection unit, there is provided an additional magnetic deflector. This deflector serves to deflect the electron beams such that, within the range of action of the deflection unit, they extend in a horizontal common plane passing through the tube axis.

Abstract: The present invention provides apparatus for forming electron beams, which may be advantageously employed in many applications, for example in display devices or thyratrons. A cathode member has a hole in its front surface. All the surfaces of the cathode member, except for the wall and base of the holes, are covered in an electrically insulating material such as glass. The cathode member and an anode member are contained within an envelope which also contains a gas filling. On application of a suitably high voltage between the cathode and anode members an electron beam is formed extensive in a direction away from the hole. The anode member may be located behind the front surface of the cathode member, and an electron beam still forms in front of the front surface.

Abstract: A device for recording or displaying images or for electron lithographic or electron microscopic uses, comprising in an evacuated envelope (1) a target (7) on which at least one electron beam (6) is focussed. This beam is generated by means of a semiconductor device (10) which comprises an electrically insulating layer (42) having an aperture (38) through which the beam passes. The layer carries at least four beam-forming electrodes (43 through 50) which are situated at regular intervals around the aperture (38). Each of the electrodes has such a potential that an n-pole field or a combination of n-pole fields is generated, where n is an even integer from 4 through 16. A suitable choice of the n-pole field will make it possible to impart substantially any desired shape to the beam (6) and thus the focus on the target.

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 beam generating system for electron tubes, particularly travelling wave tubes, is formed of a beam shaping electrode and a dispenser cathode supported therein having an emission disk at its end face. A positional change of the dispenser cathode in the beam shaping electrode at different ambient temperatures is suppressed with the beam generating system, and thus a beam defocussing is avoided. According to the invention, the dispenser cathode is directly connected to the beam shaping electron and is connected below the emission disk by means of a radial cathode support. The beam generating system of this type is particularly employed in travelling wave tubes.

Abstract: There is provided a flat cathode ray tube, wherein a plurality of individual thermionic emission cathodes symmetrically arranged at a predetermined equal spacing on a plane parallel to an image display plate, the same plurality of grids, and fluorescent anode portions which emit light by irradiation with the electrons incident therein, are inserted and sealed in a high vacuum envelope whose image display plate is transparent. For use in a color television system, the cathode ray tube further includes a system for deflecting the individual beams to appropriate color spots in the anode. There is further provided a method for manufacturing a thin television picture tube using photolithographic techniques which make possible a tube which is between 1 and 30 millimeters in thickness with the picture area of a conventional tube.