Abstract: A phosphor capable of being kept from being affected by oxygen during production thereof, carrying out luminescence due to excitation by electrons, selectively realizing various luminous colors depending on selection of starting materials and exhibiting satisfactory luminance and life characteristics. The phosphor is represented by a chemical formula Ga.sub.1-x In.sub.x N:A (0.ltoreq.x<0.8, A.dbd.Zn or Mg) and prepared by mixing starting materials containing at least an oxygen-free gallium compound and an oxygen-free doping substance to prepare a mixture and heating the mixture in a nitrogen-containing atmosphere.

Abstract: A process for manufacturing a field emission element including a substrate, and an emitter and a gate each arranged on the substrate is provided. The emitter is formed at at least a tip portion thereof with an electron discharge section, which is formed of metal or semiconductor into a monocrystalline structure or a polycrystalline structure preferentially oriented in at least a direction perpendicular to the substrate by deposition.

Abstract: A field emission cathode which is capable of increasing bond strength between emitters and a resitive layer and a method for manufacturing the same which is capable of facilitating manufacturing of the cathode. The field emission cathode includes a laminated board, which includes a substrate, and at least a cathode electrode layer, a resitive layer, an insulating layer and a gate electrode layer which are deposited in the form of a film on the substrate in order. The gate electrode layer and insulating layer are formed with through-holes so as to commonly extend through the gate electrode layer and insulating layer. The cathode also includes buffer layers made of an insulating material and formed on portions of the resistive layer exposed via the through-holes, as well as emitters arranged on the buffer layers, respectively, resulting in bond strength between the resistive layer and the emitters being increased.

Abstract: A getter device capable of being re-activated as required and arranged in a narrow space in an envelope. The getter is arranged in a layer-like manner in an envelope of an electronic element to provide, in the envelope, a film-like getter for keeping an interior of the envelope at a vacuum. Electrons emitted from an electron feed section are impinged on the getter to activate it. The getter activated adsorbs thereon gas in an envelope of an image display device.

Abstract: A getter support capable of permitting a getter to be compactly arranged in a vacuum envelope while keeping a space for the getter minimized. The getter support includes holders for vertically interposedly holding a getter, first support legs formed integrally with the holders so as to downwardly extend therefrom, and second support legs formed integrally with the holders so as to upwardly extend therefrom. The getter support is fixedly arranged in a getter chamber while being pressed by elasticity of the second support legs. The second support legs are varied in deflection depending on contact thereof with a second substrate of an envelope. This permits a distance between an upper surface of the getter and the second substrate of the envelope to be constantly kept at a desired value.

Abstract: A vacuum airtight envelope capable of being manufactured in bulk and with increased yields. Cathode substrates and anode substrates are prepared by multisubstrate co-formation techniques. A cathode source plate is cut into a plurality of individual cathode substrates, which are mounted on an anode source plate by surface-mounting. Then, getter boxes are temporarily fixed on the anode source plate and then sealedly joined thereto together with cathode substrates. Then, the anode source plate is cut, to thereby provide individual envelopes, which are then evacuated to a vacuum.

Abstract: A low-velocity electron excited phosphor having a composition represented by a general formula ZnO.multidot.(Al.sub.x, Ga.sub.1-x).sub.2 O.sub.3 :Mn, wherein X=0.001 to 0.3 mol. A content of Al in the phosphor is set be to within a range between 0.001 mol and 0.3 mol. The range permits a variation in luminance of the phosphor to be within .+-.30% and initial luminance of the phosphor to be significantly increased, resulting in the phosphor being suitable for use for a fluorescent display device.

Abstract: A field emission element including a gate and an emitter and capable of penting any of the element oxide layer from being formed on a tip of the emitter to prevent a decrease in emission current, unstable operation and an increase in noise. The gate has a surface formed of a material of oxygen bonding strength higher than that of a material for at least a tip surface of the emitter, so that oxygen atoms and molecules containing oxygen entering the gate may be captured by adsorption on the gate to prevent formation of any oxide layer on the emitter. When a portion of the emitter other than the tip surface is formed of a material of oxygen bonding strength higher than that of the material for the tip surface, formation of any oxide layer on the tip surface of the emitter is minimized.

Abstract: A field emission type fluorescent display device capable of carrying out luminous display with increased reliability at an anode voltage 200V to 1000V and providing a desired luminous color by means of a filter. The fluorescent display device includes a luminous display section consisting of three display elements. The display elements include filters of red, green and blue colors on which light-permeable anode conductors are deposited, respectively. Then, the anode conductors have phosphors of the same colors as the filters deposited thereon, respectively. The blue phosphor is made of ZnO:Zn substantially containing a blue color component. Thus, a combination of the blue filter and phosphor provides light of a blue color with increased efficiency.

Abstract: A fluorescent display device capable of being sealed while being evacuated to a high vacuum without independently forming any evacuation hole at an electrode formation section of a substrate of an envelope. A cathode substrate is sealedly formed of an electrode formation section of a large plate-like shape provided thereon with a field emission cathode, an evacuation section of a small plate-like shape formed with a cutout, and a seal member. An anode substrate on which a display section is spacedly arranged oppositely to the cathode substrate. A getter chamber including an evacuation tube is connected to the evacuation hole. Thus, the present invention eliminate independent formation of any specific evacuation at the electrode formation section, to thereby prevent damage and contamination of the substrates.

Abstract: A field emission type electron source capable of permitting a resistance value between a cathode wiring and each of emitter cones to be set at substantially the same level and increasing packaging density of the emitter cones. The electron source includes stripe-like cathode wirings arranged on an insulating substrate. The cathode wirings each are formed with a plurality of windows, so that a plurality of island-like cathode conductors and resistance layers different in resistance value from each other are formed separate from the cathode wiring. Then, a resistance layer, an insulating layer and a gate electrode are formed thereon. The gate electrode and insulating layer are formed with apertures in a manner to be common to both, in which the emitter cones are arranged, resulting in emission of electrons from the emitter cones of each group unit being rendered uniform.

Abstract: A field emission type fluorescent display device capable of exhibiting high luminescence under a low voltage while minimizing leakage luminescence and color mixing, to thereby improve display quality. An anode and a field emission cathode are arranged opposite to each other and the cathode is divided into a plurality of unit regions in a matrix-like configuration, which are matrix-driven, resulting in a display being selectively carried out. The unit regions each are divided into a plurality of subregions and the cathode and anode are divided into a plurality of strip-like electrodes perpendicular to each other, respectively. The strip-like electrodes each correspond to each of subregions and are commonly connected to each other at every second interval. Also, a focusing electrode may be arranged between the gate and the anode so as to surround the unit regions.

Abstract: A phosphor heat-treating method and an apparatus therefor capable of providing a phosphor exhibiting improved crystallizability and increased in concentration of a luminous center therein. A phosphor is heated and rapidly cooled in atmosphere gas of a predetermined pressure. The pressure substantially restrains decomposition and scattering of the phosphor during heating and cooling of the phosphor.

Abstract: An image display device including a field emission element capable of preventing diffusion of electrons to be impinged on a display section. An anode substrate is provided thereon with a phosphor-deposited display section and a cathode substrate is provided thereon with field emission elements including cathode conductors, emitter electrodes and gate electrodes. The cathode conductors and gate electrodes are formed into a stripe-like shape and arranged so as to intersect each other to form a matrix. A stripe-like diffusion prevention electrode is arranged between each adjacent two of the gate electrodes. The emitter electrodes selected by the gate electrodes and cathode conductors emit electrons. The diffusion prevention electrodes on both sides of each of the gate electrodes selected are applied thereto a voltage lower than a voltage of the gate electrodes, so that the electrons may be impinged on the display section required without diffusion, to thereby permit picture cells required to emit light.

Abstract: Electron excited luminous element capable of ensuring satisfactory emission characteristics of emitters for an extended period of time. A hydrophobic insulating film is formed on a glass anode substrate so as to cover an exposed portion thereof between anode electrodes. This keeps the glass anode substrate from being directly attacked by electrons, to thereby prevent decomposition of water and the like contained in a surface of the glass, resulting in oxygen which causes deterioration in emission characteristics of emitter cones being kept from being released from the glass.

Abstract: An image display device including a field emission element capable of preventing diffusion of electrons to be impinged on a display section. An anode substrate is provided thereon with a phosphor-deposited display section and a cathode substrate is provided thereon with field emission elements including cathode conductors, emitter electrodes and gate electrodes. The cathode conductors and gate electrodes are formed into a stripe-like shape and arranged so as to intersect each other to form a matrix. A stripe-like diffusion prevention electrode is arranged between each adjacent two of the gate electrodes. The emitter electrodes selected by the gate electrodes and cathode conductors emit electrons. The diffusion prevention electrodes on both sides of each of the gate electrodes selected are applied thereto a voltage lower than a voltage of the gate electrodes, so that the electrons may be impinged on the display section required without diffusion, to thereby permit picture cells required to emit light.

Abstract: A method for sealedly forming an envelope and an apparatus therefor capable of sealedly bonding an anode substrate and a cathode substrate to each other while preventing misregistration therebetween. A sealing glass material is arranged on a periphery of one of the substrates and the other substrate is put on the one substrate. Then, both substrates are registered with each other and then a laser beam is downwardly irradiated on the sealing glass material through the anode substrate to locally melt the sealing glass material, to thereby temporarily bond both substrates to each other. Then, both substrates are heated in an oven, to thereby sealedly bonded to each other, resulting in sealedly forming an envelope.

Abstract: A resistive element is provided which is used on a cathode conductor side of a field emission type fluorescent display device and made of a hydrogenated amorphous silicon film. Nitride is added during deposition of the hydrogenated amorphous silicon film containing an impurity for controlling resistivity of the film. A method for producing the resistive element and an apparatus therefor are also disclosed.

Abstract: A getter device capable of being re-activated as required and arranged in a narrow space in an envelope. The getter is arranged in a layer-like manner in an envelope of an electronic element to provide, in the envelope, a film-like getter for keeping an interior of the envelope at a vacuum. Electrons emitted from an electron feed section are impinged on the getter to activate it. The getter activated adsorbs thereon gas in an envelope of an image display device.

Abstract: A field emission element including an electrode structure made of a thin film exhibiting increased adhesive strength. A thin film of niobium nitride (NbN) is formed on a glass substrate by sputtering or the like. The NbN film exhibits increased adhesive strength to a degree sufficient to prevent etching for formation of the film into electrodes from causing peeling of the film.