Abstract: A super-high pressure mercury lamp with an internal pressure during operation of one hundred and some dozen atm, which has a new arrangement in which in the hermetically sealed portions neither damage the lamp nor shortening its operating service life is achieved, in a high pressure mercury lamp in which a silica glass discharge vessel contains a pair of spaced apart, opposed electrodes and which is filled with a rare gas and with mercury in an amount of greater than or equal to 0.16 mg/mm3, and in which the wall load is greater than or equal to 0.

Abstract: To reliably prevent the appearance of cracks in the sealing tube, a short-arc discharge lamp having a bulb with a light-emitting tube and sealing tubes connected to both sides of the light-emitting tube, with an anode and a cathode positioned facing each other within the light-emitting tube on the ends of electrode rods that pass through sleeve material that is supported by the sealing tubes, in which short-arc discharge lamp molybdenum foil is located between the sleeve material and the sealing tube, the outer surface of the molybdenum foil which faces the sealing tube has a surface treatment with a high-melting-point, oxidation resistant metal. The high-melting-point metal is preferably chosen from among tungsten, rhenium, tantalum, rhodium and platinum.

Abstract: A vessel has a main body and a plugging members made of alumina. First composite electrode has a cylindrical current conductor having substantially same diameter as a diameter of the opening portion at one end of the vessel, and an electrode jointed by welded at a bottom of the current conductor exposed to inside of the vessel. The current conductor of the first composite electrodes has a cylindrical member made of alumina and a metallization layer made of molybdenum and alumina. A ceramic discharge tube is made in that the vessel and a first composite electrode have been subjected to a co-firing into an integrated body, with the first composite electrode inserted into the opening portion at one end of the vessel so that the electrode is exposed to the inner space with one end of the first composite electrode is exposed to outside of the vessel.

Abstract: The invention relates to a metal component for discharge lamps, having a support of niobium or tantalum or of alloys based on niobium and/or tantalum, as well as a discharge lamp. The present invention is addressed to the problem of increasing the resistance to oxidation and corrosion of metal components having a support of niobium or tantalum or of alloys based on niobium and/or tantalum which are disposed in or on discharge lamps. The problem is solved according to the invention in that the support has a coating of one or more single layers which is formed of at least one noble metal and/or from a noble metal alloy.

Abstract: The object of the invention to devise an electrical insertion body for a tube lamp in which sealing bodies of an electrically conductive inorganic material component and a dielectric inorganic material component and upholding parts of the electrodes are attached securely to one another by sintering, and in which neither leaks nor falling out of the upholding parts of the electrodes occur.

Abstract: An electrode is fixed hermetically to one end of a conductive tube with a titanium solder and the other end of the conductive tube is closed. Thus, the conductive tube has an airtight structure and an argon gas is sealed therein. This conductive tube is fixed hermetically to a transparent alumina tube using a sealer. Further, sodium amalgam is provided at an inner end of the transparent alumina tube. The conductive tube is prevented from being deformed and sodium of a luminescent material is positioned inside the discharge tube, thus providing a high-pressure sodium lamp in which a lighting color and lamp voltage are prevented from varying during the lamp lifetime, the time required for reaching a stable lighting state after turning on the lamp is short, and the variation in lamp voltage is suppressed.

Abstract: A joined structure and joining method of a member of a ceramics or a cermet and a member of a metal such as molybdenum, in which the members may be joined with a high strength, the joined structure has improved air-tightness and resistance to corrosion and repeated thermal cycles does not result in the fracture of the joined structure.

Abstract: The electric lamp comprises a lamp vessel (1) in which an electric element (2) is arranged. The electric element (2) is connected to feedthroughs (3, 4) that extend through the wall of the lamp vessel (1). The respective feedthroughs (3, 4) comprise a metal shell (7) and an internal current conductor (13) connected thereto. The metal shell (7), which has no knife edge, clamps around the neck-shaped end portion (5, 6) of the lamp vessel (1), hence realizing the gastightness of the feedthrough.

Abstract: To provide a high tension connection portion structure for an ignition device for an internal combustion engine, which may prevent an instantaneous breakdown of the connection even if an external force is applied to a high tension connection portion, may enhance a connection property of the high tension connection portion by suppressing a sliding movement between metal terminals of the connection portion and may be applied to the path of a minute current such as an ionic current or the like, a connecting structure of a high tension connection portion used in an ignition device for an internal combustion engine, includes: a first high tension connection terminal 2; a second high tension connection terminal 4 for electrically connecting with the first high tension connection terminal 2; a locking mechanism 2a provided between the first high tension connection terminal 2 and the second high tension connection terminal 4 for restricting the separation therebetween in the axial direction; and a spring member 7 dis

Abstract: An electricity introducing member for a tube lamp includes a closing member and an electrode upholding part formed integrally together; the closing member includes a plurality of layers each comprising a conductive component and silica, the volumetric proportion of the silica being n1, n2, n3, . . . , nx such that n1>n2>n3> . . . >nx, are successively laminated in the form of a cylinder, so that the closing member serves as a functional gradient material; where the diameter of the closing member is D in mm and the total thickness of the laminate of the layers each containing more than 80 volume % of silica is L in mm; L/D is not less than 2: the electrode upholding part is shrink-fitted from the surface on the side of the layer n1 up to the layer containing at most 80 volume % of silica in the closing member. Preferably, where the diameter of the electrode upholding part is d in mm, the ratio of d/D is from 0.12 to 0.6.

Abstract: A ceramic lamp in which the hermetically sealing bodies of electrically conductive cermet are sealed to hermetically sealed tube portions of the lamp vessel with a sealing material is arranged and provided with material components designed to give the hermetically sealing portions a high reliability.

Abstract: A cathode-side first sealed portion (14) and an anode-side first sealed portion (15) are respectively provided at the two opposing ends of a discharge space (21) of a discharge casing (11). A middle chamber (16) filled with a rare gas is provided adjacent to the anode-side first sealed portion (15). A second sealed portion (18) is provided adjacent to the middle chamber (16). Each sealed portion (14),(15),(18) is airtightly sealed by the pinch sealing method. A cathode (22) is welded to a metal foil conductor (24) disposed in the cathode-side first sealed portion (14). An anode (23) is welded to a metal foil conductor (32) disposed in the anode-side first sealed portion (15). The metal foil conductor (32) in the anode-side first sealed portion (15) and a metal foil conductor (35) in the second sealed portion (18) are connected to each other by means of a lead wire (33) passing through the middle chamber (16).

Abstract: A sealing body (5) of a tube lamp using a functional gradient material in which proceeding from electrically conductive areas into the vicinity of welds on one side tube (2) and in outer leads (6) oxidation is suppressed, and in which the service life of the tube lamp is prolonged. The sealing body (5) of a tube lamp consist of a functional gradient material which is formed by mixing of a dielectric material and an electrically conductive material, the mixing ratios in the longitudinal direction being different continuously or incrementally, and in which one end forms a dielectric area and the other end forms an electrically conductive area, and by at least one part of the external surface of this electrically conductive area and/or at least one part of outer lead (6) projecting from sealing body (5) being jacketed with an atmosphere shielding layer (7).

Abstract: A high-pressure discharge lamp includes a ceramic discharge vessel which encloses a discharge space containing two electrodes and an ionizable filling including a metal halide. The discharge vessel includes a central cylindrical part with an end, and an end part closing the cylindrical part at the end in a gastight manner. The discharge vessel also has a projecting plug connected to the end part in a gastight manner for enclosing a feedthrough conductor. The end part is monolithic and its outside surface includes an angle A with the longitudinal axis of the discharge vessel at the projecting plug, where the angle A is between 30 and 60 degrees. The outside surface of the end part may be shaped like a truncated cone with a base extending radially outward. Alternatively, the end part includes two concentric tubular portions which are interconnected in a gastight manner.

Abstract: A high-pressure discharge lamp includes a glass housing made of a high-melting vitreous material, a pair of sealing components made of the same high-melting vitreous material and extended from the glass housing. A rare gas and a material that is solid or liquid at room temperature is sealed inside the glass housing. Electrically conductive bars are embedded in the sealing components. The air-tight seals around the electrically conductive bars are formed such that at least one metal material selected from metals and oxides of said metals is provided near the regions lying between the high-melting vitreous material and the electrically conductive bar.

Abstract: The present invention provides a high-voltage discharge lamp having an internal volume of 0.05 cc or less that is small yet maintains a desirable lifetime and a high luminous efficiency, a high-voltage discharge lamp device using the lamp, and a lighting apparatus using the lamp. The high-voltage discharge lamp comprises a ceramic discharge vessel that has a spherical, bulging section and a pair of small diameter cylindrical sections. The spherical, bulging section surrounds a discharge space. The small diameter cylindrical sections are connected to the ends of the spherical, bulging section. Electrode-integrated power-supplying conductors are used. Each conductor comprises a seal part and a halide-resistant part. The halide-resistant part having a proximal end connected to the distal end of the seal part. The distal end of the halide-resistant part projects into the spherical, bulging section of the translucent ceramic discharge vessel forming an electrode.

Abstract: To close off tubular ends (6a, 6b) of a metal-halide discharge vessel, a plug (11) having at least four, and preferably six or more, axially arranged layers or strata (11a-11d; 21a-21f) of a cermet, in which the metal content of the cermet of the respective layers or strata increases from the layer or stratum closest to the discharge space of the vessel to the outside. The innermost layer or stratum is directly sintered to the ceramic discharge vessel, typically of aluminum oxide, whereas the outermost layer or stratum has a metal content of such an extent that it can be welded, and is welded, to a metallic or cermet lead-through or feed-through (9, 20, 30, 35) leading through a central opening in the respective layers or strata of the plug. The outermost layer of the plug, preferably, has at least 50%, by volume, of metal, preferably of the same material as that of the lead-through in the cermet, and may even be made entirely of metal, to ensure a tight, easily made weld connection.

Abstract: At least at one end of a discharge lamp, for example a metal-halide discharge lamp or a sodium high-pressure discharge lamp, which has a ceramic discharge vessel (4), a feed-through (9, 10; 30) is provided which includes a cermet. The cermet may be in pin or capillary tube form, and has a metal content which is so high that it can be welded like a metal. The cermet can be directly sintered into an end plug (26) or into an end portion (34a, 34b) of the vessel itself. The seal thus is effected by a sealing arrangement (11, 21, 34a, 34b, 31) devoid of glass melt, which would be degraded by attack of corrosive fills within the lamp, while additionally having the capability of withstanding higher operating temperatures.

Abstract: Sealing body for a discharge lamp which consists of a functional gradient material in which one side is rich in dielectric component and the other side is rich in electrically conductive component, and which is sealed by a side tube which is connected to the arc tube of the discharge lamp and by its areas which are rich in a dielectric component, characterized in that in this sealing body an upholding part of an electrode with a tip provided with an electrode is shrink-fitted, and that furthermore on the outer peripheral surfaces of the areas of the sealing body which are rich in dielectric component, surfaces are formed which run obliquely with respect to the center axis of the above described discharge lamp so that the maximum width of the end face of the sealing body on the side of the emission space becomes smaller than the maximum width in one direction perpendicular to the axis of the sealing body and becomes greater than the diameter of the upholding part of the electrode.

Abstract: A vessel has a main body and a plugging members made of alumina. First composite electrode has a cylindrical current conductor having substantially same diameter as a diameter of the opening portion at one end of the vessel, and an electrode jointed by welded at a bottom of the current conductor exposed to inside of the vessel. The current conductor of the first composite electrodes has a cylindrical member made of alumina and a metallization layer made of molybdenum and alumina. A ceramic discharge tube is made in that the vessel and a first composite electrode have been subjected to a co-firing into an integrated body, with the first composite electrode inserted into the opening portion at one end of the vessel so that the electrode is exposed to the inner space with one end of the first composite electrode is exposed to outside of the vessel.

Abstract: In sealing body (6) of a tube lamp which seals side tube (3) which is connected to arc tube (2) and which securely holds upholding parts (7) of the electrodes by a shrink seal and which consists of a functional gradient material, in which an electrically conductive component and a dielectric component in the axial direction of the tube have a continuous or gradual concentration gradient, and in which one side is dielectric and the other side is electrically conductive, the object of the invention is achieved by upholding parts (7) of the electrodes being located in an opening of this functional gradient material without a gap in a shrink seal, and by the surface of the area of upholding parts (7) of the electrodes which are located in the opening of the functional gradient material being coated at least partially with thin layer (9) of a metal with a high melting point.

Abstract: An arc discharge tube has electrodes supported by hollow electrode support tubes at each end. A slot is formed in the electrode support tube. One edge of the slot is depressed inwardly to form a concave surface. The slot is located adjacent to the end cap of the arc tube and provides access to the interior of the electrode support tube. After the electrode assembly is sealed into one end of the arc tube, amalgam particles are dispensed into the arc tube. The arc tube is agitated rapidly, causing the amalgam particles to pass through the slot and drop into the interior of the electrode support tube. The amalgam particles are isolated from heat during sealing of the other end of the arc tube.

Abstract: The high pressure discharge lamp comprises a ceramic discharge tube containing an ionizable luminescent material and a starting gas filled in the inner space thereof, a clogging member having through-holes, and at least a portion of which being fixed on the inner side of the end portion of the ceramic discharge tube, an electric conductor having an electrode system inserted in the through-holes of the clogging member, and a sealing material layer. Preferably, the sealing material layer 16A is made of a metallizing layer. In addition, the high pressure discharge lamp comprises the ceramic discharge tube, the clogging member, the electric conductor inserted in the through-holes of the clogging member, and a metallizing layer for sealing provided so as to join to the clogging member and the electric conductor.

Abstract: A high pressure discharge lamp comprising a ceramic discharge tube having an inner space filled with an ionizable light-emitting material and a starting gas, plugging members each at least partially fixed to an inner side of respective one of end portions of the ceramic discharge tube and each having a through-hole provided therein, conductive members inserted into or through the through-holes of the plugging members, respectively, and electrode units provided in said inner space, wherein a material of the plugging members is the same as that of the ceramic discharge tube, and each of the plugging members is gas-tightly joined to the corresponding conductive member with a metallizing layer.

Abstract: This invention involves a new type of feedthrough-plug member for metal halide HID lamp using PCA envelopes. The construction of the lamp housing consists of a PCA envelope and specially designed radially graded alumina-metal cermet multi-layers to eliminate cracking in cermet or PCA due to thermal stresses arising from thermal expansion mismatch. The fills are metal halides such as Na-Sc-I, rare earth halides, Hg, Sn, and inert gases. The PCA vessel and directly sealed cermetfeedthrough assemblies allow the metal halide lamps to operate at high wall temperatures with better lumen output, color temperature, and CRI.

Abstract: A method of making a ceramic arc tube for a metal halide lamp comprises the steps of forming as an integral unit a hollow body having one open end and a substantially closed end. The substantially closed end includes an outwardly extending capillary tube having an electrode receiving aperture therein that communicates with the hollow body. An end cap is then formed for closing the open end. The end cap comprises an annular portion and an extending capillary tube, The end cap is fitted into the open end of the hollow body to form a pre-assembly. The pre-assembly is then fired to seal the end cap to the hollow body to form an assembly and the assembly is subsequently fired to sinter the same.

Abstract: To prevent corrosion of the sites where upholding parts of electrodes are attached and to easily effect exact positioning of the electrodes, in a discharge lamp in which the sealing tubes of a discharge vessel are sealed with sealing bodies of material with a gradient function which is formed from a dielectric powder of the same material as material of the discharge vessel and from a conductive powder, the upholding parts of the electrodes extend through axial openings which are formed in the sealing bodies and are attached and hermetically sealed on the outer faces of the sealing bodies by means of a solder or the like.

Abstract: There is provided a preform for a fluorescent lamp comprising a bulb and a stem provided with a filament and a discharge electrode and a fluorescent lamp prepared by the preform without an exhaust pipe for use as an indicating lamp, the fluorescent lamp being sealed after exhausting inside air and charging inert gas and mercury through an appropriate space formed between the bulb and the stem inserted into the bulb. Thus, even when liquefied mercury is present in the discharge chamber, it receives a large amount of heat from the filament applied voltage and is easily and quickly evaporated, whereby the characteristics of the lamp become stable quickly after turning on the lamp.

Abstract: The electric lamp has a glass lamp vessel (1) having seals (3) from which an external metal wire (6) extends. A bare corrosion resistant contact wire (7), having a specific resistance of less than 0.8 .mu..OMEGA.m and a hardness of 50-300 HV is welded, e.g. butt-welded to the external metal wire (6). The contact wire (7) has an axial free end portion (8). An transversally extending intermediate portion (9) may be present between the seal and the free-end portion (8). The lamp allows secure electrical connections to a luminaire easily and rapidly to be made.

Abstract: A discharge lamp arc tube comprises: a glass tube having a linear extension portion, a closed glass bulb, and pinch seal portions at both sides of the closed glass bulb; and electrode assemblies, each having an electrode rod, a molybdenum foil and a lead wire integrally series-connected, the molybdenum foil having oxide films thereon, wherein the electrode assemblies are inserted into the glass tube and pinch-sealed such that the molybdenum foils are positioned at the respective pinch seal portions.

Abstract: This invention involves a new type of feedthrough-plug member for metal halide HID lamp using PCA envelopes. The construction of the lamp housing consists of a PCA envelope and specially designed axially graded alumina-metal cermet multi-layers to eliminate cracking in cermet or PCA due to thermal stresses arising from thermal expansion mismatch. The fills are metal halides such as Na--Sc--I, rare earth halides, Hg, Sn, and inert gases. The PCA vessel and directly sealed cermet-feedthrough assemblies allow the metal halide lamps to operate at high wall temperatures with better lumen output, color temperature, and CRI.

Abstract: A medium pressure quartz lamp for arc discharge illumination, includes a quartz envelope having opposite electrode ends with an electrode unit sealably attached to each of the opposite electrode ends. Each of the electrode units includes an electrode rod extending into the envelope and a platform physically attached to the rod. The platform has a melting point of at least 1,000.degree. C. The electrode units also include at least one conductive, elongated metal foil which has a first end and a second end. The conductive elongated metal foil(s) are attached at their first end to the platform and attached at their second end to a terminal connector. Preferably, plural foils are utilized with a single platform attached to the electrode rod at their first ends and attached to a plurality of terminal connectors a their second ends.

Abstract: A DC glow discharge lamp is disclosed, in which one the pinch seal portions of an arc tube of quartz glass with an anode and a cathode arranged therein in opposed relation to each other is bonded to a base by means of a ceramic adhesive containing a binder, and a conductive member connected around the cathode-side pinch seal portion is mounted in such a manner as to assume the same potential as the cathode. Even in the case where the binder mixed in the ceramic adhesive for improving the bonding strength is vaporized, it attaches to the conductive member and assumes a negative potential and thus is prevented from attaching to the cathode-side pinch seal portion. The devitrification of the pinch seal portion or the leakage therefrom which otherwise might occur due to the binder are thus suppressed, thereby providing a DC glow discharge lamp with an improved service life.

Abstract: A high pressure discharge lamp including: (1) a ceramic discharge tube having an interior space filled with an ionizable light-emitting material and a starting gas, the ceramic discharge tube including a main body and at least one end portion connected to an end of the main body, a corner being formed between an inner surface of the main body and an inner surface of the at least one end portion; (2) a sealing member at least partially fixed inside the at least one end portion, a through-hole being formed through the sealing member; and (3) a current conductor inserted through the through-hole of the sealing member, wherein a storing recess for storing said ionizable light-emitting material as a liquid phase therein is formed at a surface of the sealing member on a side of the interior space.

Abstract: A sealing structure for a light-emitting bulb assembly includes a closure, having a core which serves as an electrode for sealing an open end of a bulb. The closure includes a bulb-side region disposed adjacent to the open end of the bulb and made of a compositional ingredient having a coefficient of thermal expansion which is substantially the same as that of the bulb, a core-side region disposed adjacent to the core and made of a compositional ingredient having a coefficient of thermal expansion which is substantially the same as that of the core, and an intermediate region disposed between the bulb-side region and the core-side region and made of a compositional ingredient having compositional proportions adjusted such that a coefficient of thermal expansion thereof varies gradually from the coefficient of thermal expansion of the bulb-side region toward the coefficient of thermal expansion of the core-side region.

Abstract: The invention relates to a high-pressure discharge lamp provided with a discharge vessel which encloses a discharge space, which has a ceramic wall, and which is sealed at one end by means of a projecting ceramic plug which encloses with clearance a current supply conductor to an electrode arranged in the discharge vessel and is connected to said conductor adjacent an end facing away from the discharge space in a gastight manner by means of a melting-ceramic connection. According to the invention, at least an end portion of the ceramic plug situated near the end facing away from the discharge space is impermeable to light.

Abstract: A fluorescent lamp has a protective assembly that includes a protective tube preformed from a semi-rigid non-frangible polymeric transparent or translucent material that is stabilized against ultraviolet radiation. The protective tube has a body portion received over the glass tube with a clearance sufficient to enable the glass tube to be slid into the protective tube and a closure portion at each end that is mechanically and thermally deformed permanently to engage an adhesive layer on the terminal cap of the lamp and form a bond therewith such as to provide a mechanical connection that resists separation of the terminal cap from the protective tube and a moisture barrier and hermetic seal between the lamp and the protective tube.

Abstract: A high pressure sodium lamp is provided. The high pressure sodium lamp includes a discharge lamp vessel to the ends of which a pair of electrodes are respectively connected, a sleeve coupled to at least one end of the discharge lamp vessel and connected to one of the electrodes, a wire frame slidably inserted into the sleeve, and a buffer coil, one end of which is connected with the wire frame and the other end of which is housed inside the sleeve, elastically supporting the discharge lamp vessel.

Abstract: To provide a tight seal for a fill bore in the wall or an end plug of a dharge vessel for high-pressure discharge lamps, a fill bore is provided either through the wall--in the region of the plug--or through a plug, and the fill bore is then closed by a stopper in combination with a melt sealing material, which is so chosen that the sealing material and plug-like member combination provide a minimum of sealing material exposed to the fill in the discharge volume. The fill in the discharge volume of the discharge vessel is ionizable and, for example containing halides, is highly corrosive to the sealing material. The lamp can be made by inserting a stopper into the filling bore, applying, with the stopper in place in the filling bore, sealing material to the outer end of the filling bore, and heating the portion of the discharge vessel to liquefying temperature of the sealing material to liquefy the sealing material and hence close off the fill bore.

Abstract: A metal halide lamp comprises a sealed tube containing mercury vapor and halide, and electrodes extending to a center of the sealed tube, supported by sealed portions at both ends of the sealed tube. A notch extending in a direction perpendicular to an axis of the electrode is formed in each electrode. A transverse cross sectional area of a portion where the notch is formed is smaller than the transverse cross sectional area of another portions and functions as a heat dam portion for damming heat. Accordingly, temperature of a proximal portion from the heat dam portion to the support portion is lower than that of the same portion of the conventional electrode, and temperature of a distal end portion is higher than that of the same portion of the conventional electrode. Thus, formation of low-melting alloy due to reaction of the proximal portion of the electrode and the metal halide can be suppressed.

Abstract: A high pressure discharge lamp having an extended life includes a discharge vessel 8, and a feedthrough 10 extending through a plug 11. A directly sintered connection is formed between the feedthrough 10 and the plug 11 wherein sealing material 7 is provided covering the area surrounding the feedthrough on the outer surface of the plug 11. The plug 11 is formed of a composite material whose thermal expansion coefficient lies between that of the ceramic vessel and of the metal feedthrough.

Abstract: A vacuum-tight seal, particularly for an arc tube or discharge vessel for a metal halide or sodium high-pressure discharge lamp, is made by forming the arc tube of transparent ceramic, typically Al.sub.2 O.sub.3, having two open ends, into which connecting plugs (3), with central openings, are sealed. Open metal tubes (4) fitting into the openings of the plugs (3) are then vacuum-tightly sintered therein. An electrode system (5, 10, 10'), forming a subassembly with a current supply lead or lead-through (6, 11, 14, 15, 20, 24) is provided, having an outer diameter fitting into the metal tube.

Abstract: To provide an effective seal for a metal-halide discharge lamp having a ceramic discharge vessel (4), the seal is formed in multiple parts, in which a first part, adjacent the interior or discharge side of the vessel, includes a melt component (14a) which is highly resistant to attack by metal halides within the fill of the lamp. It may contain only 0-12%, by weight, of SiO.sub.2 and has a high melting point, in the order of between 1500.degree.-1700.degree. C. The melt-in region remote from the discharge side is melt-sealed by a vitreous composition (14b), devoid of pores, voids, bubbles, fissures or cracks, to form an effective, vacuum-tight seal, and protected from attack by the metal halides by the mechanically less stable seal in the first zone. The second composition has a much lower melting point, for example in the order of between 1200.degree.-1400.degree. C., and has 20-40% SiO.sub.2.

Abstract: A metal halide arc discharge lamp includes a sealed outer envelope, an arc tube located within the envelope, a cylindrical shroud positioned around the arc tube, stops positioned at ends of the shroud to capture the shroud therebetween, and conduction wires which both provide electrical energy to the arc tube and mechanically support the arc tube and the shroud. The outside diameter of the shroud is maximized in relation to the inside diameter of the neck of the outer envelope such that the shroud can be inserted through the neck during manufacture of said lamp. In order to reduce electrolytic sodium loss, a conductor wire passing through the shroud in close proximity to the arc tube is surrounded by a ceramic sleeve to electrically insulate the conductor wire from the arc tube, and the stops are ceramic to electrically insulate the shroud from the conductor wires.

Abstract: To provide a sealed through arrangement for electrical leads through a ceramic end plug, suitable for discharge lamps of between about 50 to 250 W power rating, the lead-through (9) is made of a material having a thermal coefficient of expansion which is substantially less than that of a ceramic sealing plug (10), for example of tungsten, molybdenum or rhenium, but so small that the individual, actual expansion of the ceramic material will not cause separation from the metal, and/or a glass melt, ceramic melt or sintar connection therewith. The electrical connection is formed by at least two, and preferably more than two, thin wires or pins (23) having a diameter, each, of up to only about 0.25 mm, and preferably less. Each of the wires, then, will carry currents in the tenths ampere ranges, sufficient for operation of the lamp, and passed through melt-sealed capillary openings in the ceramic sealing plug (10).

Abstract: To provide a tight seal between an essentially solid niobium or tantalum necting pin or rod (10) passing through an opening (7, 28) in an end plug (11) closing off a high-pressure discharge lamp discharge vessel (8), the pin or rod is formed with two axial portions, one of which has externally projecting continuous rings (17), preferably two or three, or an externally projecting thread (26). The rings or thread are press-fitted into the end portion of the bore in the plug, which deforms the edge (20) of the rim, ridge or thread, or shears off the edge portion, ensuring a tight preliminary fit in the bore; sealing glass, which is then melted to fill a capillary space between the pin or rod and the plug, is protected by the preliminary seal against corrosion or attack from the fill within the discharge lamp; if the projection is in form of a thread, glass can penetrate within the threads to further seal and retain the pin or rod.

Abstract: A lamp inlead assembly for a light source having a lamp envelope with at least one end region in which the lamp inlead assembly is sealably disposed includes and outer lead wire member to which power to the light source is coupled, an inner lead wire member to which the light generating device is connected, whether incandescent or discharge, and a thin foil member disposed therebetween on which the inner and outer lead wire members are fixedly secured. The thin foil member is constructed of molybdenum and is essentially uniform in thickness throughout.

Abstract: Alumina arc tube sealing members including a highly pure, fine alumina doped with yttrium oxide, and magnesium oxide. The sealing members are used in the formation of sintered hermetic seals to a green, prefired, or fully sintered translucent alumina arc tube and niobium electrical feedthrough assemblies with or without the use of sealing frits or brazing alloys.

Abstract: A high-pressure discharge lamp of the invention includes a ceramic discharge vessel (10) in which a first and a second electrode (40a, 40b) are arranged and which encloses a discharge space (11 ) which is provided with a filling containing a metal halide. The discharge vessel (10) has a central zone (20) between the electrodes (40a, 40b) and a first and a second cylindrical end zone (30a, 30b) which each surround a current supply conductor (50a, 50b) connected to a respective electrode (40a, 40b). At least the first end zone (30a) has a diameter smaller than the smallest diameter of the central zone (20). The current supply conductor (50a) through the first end zone (30a) has a halide resistant portion (51a) which faces the discharge space (11) and a portion (52a) permeable to hydrogen and oxygen and facing away from the discharge space (11).

Abstract: To protect a niobium tube (9) forming a current supply lead through a thrh-opening (14) in an end plug (10) in a ceramic discharge vessel against attack by halides or condensed sodium, the through-opening is formed in two portions, of different diameters. The outer portion (16), remote from the discharge vessel, has a diameter which is matched to the diameter of the tube (9), leaving only a capillary between the plug opening and the tube; the second, inner portion (17) is narrower than the first one, that is, outer portion, and surrounds the shaft of the electrode by a sufficient distance to permit expansion of the electrode, typically of tungsten, under operating conditions, without cracking the plug by forced engagement with the wall of the inner portion (17) of the aperture. A sealing glass, melt-sealed into the capillary of the outer portion, seals the niobium tube.