Abstract: In certain embodiments, a lamp is provided with an arc envelope including a ceramic, an end member including a material different from the ceramic, and a compliant seal disposed between the end member and the arc envelope. The compliant seal includes a plurality of layers having different thermal expansion characteristics in an order of gradual change between the arc envelope and the end member.

Abstract: The invention relates to an improved electrode rod (1) holder with the aid of a metal tube piece 5 and a metal plate 6 connected in a fixed manner to the metal tube piece for a mercury ultra-high pressure discharge lamp.

Abstract: A discharge lamp for a vehicle is provided with a ceramic luminous tube, a front side electrode and a rear side electrode held by the ceramic luminous tube, a first lead wire connected to the front side electrode, a second lead wire connected to the rear side electrode, a third lead wire having a front end portion connected to the first lead wire, an outer tube, and a socket. The ceramic luminous tube, the first lead wire, the second lead wire and the third lead wire are accommodated in the outer tube. The ceramic luminous tube includes a luminous portion and a pair of small diameter tube portions. The luminous portion is formed into a substantially cylindrical shape extending in a longitudinal direction. The third lead wire includes a horizontal portion extending in the longitudinal direction above the luminous portion.

Abstract: A UV lamp comprises: a bulb (2) containing a mixture of an inert gas and metallic halides; at least one first electrode (4) and one second (4) electrode associated with the bulb (2); a connector (6), coupled to the bulb (2) and having two thin metal plates (12a) protruding from a portion of said connector (6). Each flat thin plate (12a) is electrically connected to an electrode (4) and is spaced apart from the other thin plate (12a) by at least 20 mm.

Abstract: A cement for bonding an arc tube body made of an aluminum nitride sintered body and an electrode support made of molybdenum achieves high gas tightness in the obtainable arc tube without impairing the excellent translucency of the aluminum nitride sintered body. The cement contains a molybdenum powder and an aluminum nitride powder, and the total amount of metalloid elements, rare-earth elements and metal elements (except the rare-earth elements and aluminum element) corresponding to the following conditions (1) and (2) is 300 ppm or less: (1) metal elements having a melting point of 2000° C. or lower, and (2) metal elements having an ion radius smaller than that of aluminum.

Abstract: A metal halide lamp with a more stable lamp voltage, comprising a ceramic discharge vessel which encloses a discharge space, in which a first and a second electrode are arranged, which discharge vessel has a central zone extending between the electrodes and being closed at either side by a first and a second end zone, respectively, in which the first end zone surrounds, with little clearance, a current supply conductor connected to the first electrode and extending to the exterior through a seal to the wall of the first end zone, which current supply conductor has a halide-resistant section facing the discharge space and a section remote from the discharge space, wherein the halide-resistant section of the first current supply conductor comprises a wire made of tungsten or of tungsten alloyed with molybdenum.

Abstract: A high intensity discharge lamp comprises an arc tube, which encloses an arc chamber. The arc chamber contains a gas fill and the arc tube is terminated by at least one sealed portion. The sealed portions enclose an electrode assembly. The electrode assembly comprises an electrode, a lead-in wire and an electrically conducting foil. The electrode extends into the arc chamber. The lead-in wire extends outward from the sealed portion for providing electric contact with a power supply. The electrically conducting foil connects the lead-in wire and the electrode and provides a sealed electric connection through a sealed portion of the arc tube. At least one of the electrodes is provided with surface irregularities in a region between the foil and the arc chamber in order to control shape and size of cracks in a seal wall surrounding the electrodes. In the method, an electrode of predetermined geometry and structure is provided with at least one artificial surface irregularity.

Abstract: There is described a brazing alloy having a first component comprising a source of molybdenum and a source of aluminum and a second component comprising boron, wherein a weight ratio of said second component to said first component is not greater than 1:20. The addition of boron results a substantially lower melting point than alloys employing molybdenum and aluminum alone. It is suitable for use in discharge vessels having a hollow bodies selected from the group of monocrystalline alumina, polycrystalline alumina and aluminum nitride; metallic electrode holders fitted into ends of the hollow body; and sealed thereto by a braze.

Abstract: A high-pressure mercury vapor discharge lamp (1) comprising an envelope (2) of high temperature resistant material having a discharge vessel (3) and two electrodes (5, 6) extending from two seal portions (4) into the discharge vessel (3), the two electrodes having an electrode gap (de) smaller than or equal to 2.5 mm, preferably smaller than or equal to 1.5 mm, is described. The discharge vessel (3) contains a filling which essentially comprises the following substances: rare gas, oxygen, halogen consisting of chlorine, bromine, iodine, or a mixture thereof, as well as mercury in a quantity greater than or equal to 0.15 mg/mm3? The seal portions (4) have a cross-sectional area of between 6 mm2 and 20 mm2, preferably approximately 10 mm2. A method of manufacturing such a high-pressure mercury vapor discharge lamp (1) and a projector system for such a high-pressure mercury vapor discharge lamp (1) are also described.

Abstract: Light source device, including an alternating current high-pressure mercury lamp having a pair of opposed electrodes within a spherical light-emitting part containing at least 0.15 mg/mm3 of mercury and 10?6 ?mol/mm3 to 10?2 ?mol/mm3 of halogen, and cylindrical hermetically sealed portions extending from both ends of the light-emitting part. External leads protrude from the ends of the light-emitting part. A reflecting mirror has a concave reflecting part surrounding the light-emitting part and a cylindrical neck part. An adhesive fills a periphery one of the hermetically sealed portions in the area of the external leads in a manner fulfilling the relationship L1/R?0.5 where L1 (mm) is the length along the hermetically sealed portion filled with an adhesive and R (mm) is the diameter of the hermetically sealed portions. Feed wires connect to the external leads and openings for the feed wires can be formed in the reflecting part with flexible tubes between them.

Abstract: A high pressure discharge lamp has a sealing portion that is made of glass and a sealing metal piece. In a method of manufacturing the high pressure discharge lamp, the sealing metal piece is irradiated with laser beam whose pulse width is 1×10?9 seconds or less, so as to carry out a surface treatment of the sealing metal piece. The sealing metal piece may have a groove that is 120 to 600 nm in depth and 450 to 1,200 nm in width.

Abstract: A light source capsule (16) having a capsule envelope (18) with a wall (20) defining an enclosed volume (22), and having a sealed portion (24). A light source (26) is positioned in the enclosed volume (22) and has deformable electrical leads-ins (28, 30) extending through the sealed portion (24) of the capsule envelope (18). Stiff lead-in engagers (32) are aligned with the sealed portion (24) of the capsule envelope (18) and are electrically coupled to the electrical leads (28, 30), the lead-in engagers being electrically conductive. The lead-in engagers are fitted through apertures in the base (14) of a lamp envelope (12) to complete a lamp (10).

Abstract: A high intensity arc discharge lamp having a short metal seal plug running hotter than typical of capillary seals, enables a lamp with a metal fill to achieve a vapor pressure higher than the one set by the cold spot temperature typically of a capillary seal lamp. Corrosive fill materials, such as halogens are excluded. Zinc may be used to in starting the lamp.

Abstract: A high pressure discharge lamp with a capacitive starting aid is provided. The high pressure discharge lamp may include an outer bulb; a discharge vessel that is accommodated in the outer bulb, the discharge vessel comprising at least one end with a seal in which an electrode system is fastened; a frame holding the discharge vessel in the outer bulb; and a starting aid fastened on the seal. The starting aid may have two functional parts.

Abstract: An electric lamp comprises an inner assembly including a light source and a control gear circuit. An outer envelope encloses the light source and at least a part of the control gear and has a predetermined wall thickness and an end portion. The outer envelope is comprised of two parts separated along a circumferential line. The two parts of the envelope are connectable and sealable to form a uniform outer envelope with a seal region. The seal region has a wall thickness and is merged in a surface portion of the two parts of the envelope so that the surface unevenness of the seal region is not greater than 0.5 millimeters, and the maximum difference of the wall thickness of the seal region with respect to the wall thickness of the outer envelope is not greater than 0.3 millimeters. A method for manufacturing an electric lamp as described above is also disclosed.

Abstract: An arc discharge lamp (10) having an arc tube (12) containing an arc generating and sustaining medium (13) and first and second spaced apart electrodes (14, 16), respectively. An envelope (18) surrounds the arc tube (12) and contains an atmosphere (19) within it. The atmosphere is of a composition and pressure that will provide a burst of UV radiation in response to a spark generated within the envelope (18) and, in a preferred embodiment of the invention, is selected from argon or nitrogen (with nitrogen being preferred) at a pressure of from 150 to 400 torr. First and second electrical lead-ins (20, 22) are sealed within the envelope (18), with the first lead-in (20) being electrically connected to the first electrode (14) and the second lead-in (22) being connected to the second electrode (16), for example, by connector wire (22a). Means (30) is contained within the envelope (18) and exposed to the atmosphere (19) for generating a UV-producing spark within the atmosphere (19).

Abstract: The invention relates to a discharge lamp, in particular a high-pressure discharge lamp, having a discharge vessel (1) which has two diametrically opposite necks (2, 3) into each of which a holding rod (5, 10) is fused at least in places, with an electrode (4, 9) which extends into the discharge vessel (1) being arranged on each holding rod (5, 10), and with in each case at least one annular plate (7, 12) at least partially clasping a holding rod (5, 10), with at least one of the annular plates (7, 12) being arranged in the discharge vessel (1).

Abstract: A high pressure discharge lamp having a hermetically sealed portion on opposite sides of an arc tube made of quartz glass and in which a pair of opposed electrodes is located is improved so that electrode rod warping is prevented even when the lamp is repeatedly lit and unlit. Electrode rods extending from the electrodes pass through a center hole in a respective quartz glass body which is positioned and fastened onto each the electrode rods with an infrared reflection membrane composed of a heat-resistant metal being provided on the inner surface of the center hole of the quartz glass body separating the electrode rod from the quartz glass body. The quartz glass body is integrated with the quartz glass forming the hermetically sealed portion and is positioned against a step formed at the boundary between large and small diameter portions of the electrode rod.

Abstract: A lamp (100) comprises an outer envelope (120) having first and second electrical lead-ins (140, 160) sealed into a base (180) of the envelope (120). A ceramic arc tube (200) is operatively mounted within the envelope (120), the arc tube (200) having at least one electrode (220) therein. A tubular, niobium feed-through (240) is connected to the at least one electrode (220) and sealed to the ceramic body (120) at a joint (260) that can comprise a glass frit (260a). A stainless steel rod (280) is electrically connected between the electrical lead-in (140) and the tubular niobium feed-through (240), the stainless steel rod (280) being the only electrical connection between the lead-in (140) and the niobium feed-through (240).

Abstract: To provide a configuration for a lamp with at least one base comprising a light emission element arranged in a light-emitting tube, external leads supplying energy to said light emission element, an antioxidant layer covering said external leads, sealing portions sealing metal foils connected electrically to said external leads and bases fixed via an adhesive to said sealing portions, the adhesive fixing said base does not directly contact said antioxidant layer.

Abstract: A ceramic arc body includes a main body having a chamber. A leg extends from the main body and has an internal opening therethrough that communicates with the chamber. An electrically non-conductive seal member is received in the leg opening. A tapered internal surface abuttingly engages the seal member and provides for centering of the seal member relative to the leg. A separate tapering region, shoulder, or stop surface limits insertion of the seal member into the leg opening for precision location of the seal member, and in another embodiment, a single continuous taper inside the leg cooperates with a tapered seal member for both centering and precision insertion of the seal member into the leg. In another embodiment, a hybrid electrode is employed where one portion of the hybrid electrode is electrically non-conductive and a second portion of the electrode is electrically conductive.

Abstract: A hermetically sealed lamp having at least one seal-material-free bond. The seal material-free bond may be a material diffusion bond, a mechanically deformed bond such as a cold weld or crimp, a focused heat bond such as a laser bond, or any other such bond. For example, the hermetically sealed lamp may have one or more endcaps diffusion bonded to an arc envelope, such as a ceramic tube or bulb. The hermetically sealed lamp also may have one or more tubular structures, such as dosing tubes, which are mechanically closed via cold welding or crimping. Localized heating, such as the heat provided by an intense laser, also may be used to enhance any of the foregoing bonds.

Abstract: An all-metal electron emissive structure for low-pressure lamps is disclosed. The all-metal electron emissive structure consisting of one or more metal is operable to emit electrons in response to a thermal excitation, wherein an active region of the electron emissive structure under steady state operating conditions has a temperature greater than about 1500 degree K, and wherein the cathode fall voltage in the discharge medium under steady state operating conditions is less than about 100 volts. A lamp including an envelope, an electrode including the all-metal electron emissive structure, and a medium, is also disclosed.

Abstract: An electric lamp includes a quartz-glass envelope having at least one sealed end, a thin foil including molybdenum at least partly embedded within said sealed end, a first current conductor connected to the foil extending interiorly of the envelope, and a second current conductor connected to the foil and extending exteriorly of the envelope. The re-crystallized foil exhibits a yield strength (offset=0.2%) according to ASTM F 8M-91 below 300 MPa. This can be obtained by molybdenum doped with between 0.01 and 5 wt % of rhenium or 0.01 and 2 wt % of tungsten.

Abstract: A gas-discharge lamp (1) is described having an inner envelope (2) comprising a discharge vessel (3) and two tubular sections (6, 7) arranged on the discharge vessel, having two electrodes (4, 5) that project from the tubular sections (6, 7) into the discharge vessel (3) and that, to enable them to be supplied with power, are electrically connected to respective electrical conductors (10, 11) that extend through the associated tubular sections (6, 7) and that are enclosed in the tubular sections (6, 7) with a gastight seal along a sealing section (8, 9). The lamp (1) has an outer envelope (18) that is connected at each of its ends to respective ones of the tubular sections (6, 7) of the inner envelope (2) and that surrounds the discharge vessel (3) while leaving an outer cavity (20) between itself (18) and the discharge vessel (3).

Abstract: The present invention relates to a high pressure discharge lamp that includes a pair of electrodes, which face each other in an electric discharge space. Further, an electrode axis of one of the electrodes is joined to a metallic foil in a sealing portion, and two or more grooves are formed in an axis direction on a portion corresponding to the sealing portion on the electrode axis. Furthermore, a remaining portion that lacks grooves is left on the electrode axis in a metallic foil side thereof, and the metallic foil side ends of the grooves are not aligned with each other in the axis direction thereof.

Abstract: In an ultrahigh pressure mercury lamp that encloses mercury is enclosed in an arc tube, an electrode has a head portion whose diameter is larger than that of an axis portion and a cylindrical portion formed to project from and extend, integrally with a back end face of the head portion, wherein an inner circumference face the cylindrical portion is apart from the axis portion so as to surround the axis portion. During an alternating current lighting, a relational expression of d/(1/f)×1/2?3.8 is satisfied, wherein a frequency, which relates to an anode operation period that is the longest in the anode operation period during which one electrode serves as an anode, is represented as f, and a distance in an axial direction from the leading edge position of the head portion of the electrode to a boundary position between the head portion and the cylindrical portion is represented as d.

Abstract: The present invention is an LED lighting lamp which comprises a lamp body including a light emitting part in which a plurality of LED elements are arranged on each of side surfaces of a polygonal supporting member and a connection part which is provided at a different position from that of the light emitting part and is formed with a plurality of terminal electrodes electrically connected to the LED elements, and a socket in which the connection part of the lamp body is fitted and which has a pair of output terminals electrically connected to the terminal electrodes, and which is configured to enhance reliability and long-term stability and reduce a cost involved in exchanging a light source.

Abstract: The electrode mount includes a filament coil, paired lead wires supporting the filament coil therebetween in a manner that the filament coil hangs across the lead wires; and bead glass retaining the paired leadwires. The arc tube includes an arc tube main body formed by winding a glass tube, and an electrode fixed to the end portion of the arc tube main body. For this electrode, the electrode mount is used. The fixing of the electrode mount at the end portion of the arc tube main body is made at a region of the lead wires positioned between the filament coil and the bead glass, and the bead glass is disposed outside the arc tube main body.

Abstract: A fluorescent tube in which no luminance gradient in the longitudinal direction occurs even when a one-side high-voltage driving method is used, a method of driving the fluorescent tube, an illuminating device for display device, and a display device having the illuminating device are provided. The fluorescent tube for one-side high-voltage driving is arranged behind a display panel via optical sheets. An internal diameter of the fluorescent tube is arranged to become larger gradually toward an electrode part at a high-voltage driving side, which prevents the occurrence of the luminance gradient in the longitudinal direction when a one-side high-voltage driving method is used.

Abstract: A short arc lamp comprises a body portion made from an insulating material and having a curved reflective surface, in which a concave discharge space is formed; a pair of cathode and anode disposed at a focal point of the reflective surface with a gap; a support member connected to the cathode; and an electric supply ring connected to the support member, wherein a heat release member is provided on the anode or the support member or when a heat capacity of the cathode is A and that of the support member is B, a relationship of A and B is B/A>2.8.

Abstract: The invention relates to a barrier layer provided on the electrode assembly of a discharge lamp comprising at least a layer of nanoclusters of a non-oxidizing material. Further, the invention relates to an electrode assembly for a discharge lamp comprising an electrode having a foil attached thereto to create an electrode assembly, the assembly being coated with a multi-layer coating comprising at least a layer of non-oxidizing material in the form of nanoclusters, and at least another layer of non-oxidizing material, such that the total coating thickness is up to 1500 nm.

Abstract: This projector comprises a source lamp, a lamp storage portion, storing the source lamp therein, including an air discharge opening for discharging internal air from the lamp storage portion and a netlike member so arranged as to cover the outer side of the air discharge opening of the lamp storage portion for inhibiting fragments of the source lamp from being discharged outward from the lamp storage portion through the air discharge opening when the source lamp is broken. The lamp storage portion further includes a protrusion provided on the outer side surface close to the air discharge opening to protrude in a direction intersecting with the extensional direction of the netlike member with a function of inhibiting the fragments of the source lamp from passing through a clearance between the lamp storage portion and the netlike member.

Abstract: The invention relates to a high-pressure discharge lamp (1) having a burner (2), which is provided with a starting aid device (30, 32) for improving the starting behavior. Said device is configured according to the invention as a grid (30) encompassing the burner in the region of a ceramic (6) holding the burner (2) and having contact with a power feed (24). Said grid (30) acts as a starting aid and as protection against fragments in case of a burner explosion.

Abstract: A method for producing a seal-in foil for the gas-tight electrical feed in a lamp is provided. The seal-in foil may be separated from a foil perform. The method may include forming a weakened zone and separating the seal-in foil along the weakened zone.

Abstract: A high-pressure discharge lamp may include a ceramic discharge vessel and a longitudinal axis, with electrodes respectively being led out from the discharge vessel by means of a feed-through via capillaries, wherein a tubular cermet part, which consists of individual layers of different composition layered axially in succession, is fitted on the capillary, each layer containing Mo and Al2O3, the proportion of Mo in the first layer facing toward the capillary being from 3 to 15 vol. % and in the last layer being from 85 to 97 vol. %, and a molybdenum cover cap, the cover cap being welded to the feed-through and the cover cap being connected to the cermet part by means of solder containing metal, and the connection between the capillary and the cermet part being established by means of high-melting glass solder or sinter-active Al2O3 powder.

Abstract: A vehicle discharge lamp is provided with an outer tube, an arc tube disposed within the outer tube, and a pair of electrodes disposed within the arc tube. The arc tube includes a light emitting portion, and a pair of pinch seal portions. Molybdenum foils are sealed in the respective pinch seal portions. Each of the electrodes includes a sealed portion sealed within the pinch seal portion, a projecting portion projecting into the light emitting portion, and a welding portion welded to the molybdenum foil. A concavo-convex part is formed on the sealed portion.

Abstract: A vehicular discharge lamp includes a pair of electrodes including sealed portions sealed in a pair of pinch seal portions of a light emitting tube, wherein each of the sealed portions is segmented into: a first intermediate region positioned in the middle of the electrode in an axial direction; two end regions configured as both end portions of the sealed portion in the axial direction; and two second intermediate regions positioned between the first intermediate region and the end regions, respectively, wherein concave or convex fabrication portions are formed in the second intermediate regions, and wherein a ratio of formation area of the fabrication portions to an area of an outer peripheral surface of the first intermediate region is set to be smaller than that of the formation area of the fabrication portions to an area of outer peripheral surfaces of the second intermediate regions.

Abstract: A system and method for hermetically sealing a lamp. Certain embodiments of the lamp have an arc envelope having an open end and, also, an end structure diffusion bonded to the arc envelope at the open end. The end structure also has a dosing passageway extending into the arc envelope. In other embodiments, a lighting device is provided with an end structure adapted to close an open end of an arc envelope, and a dosing tube diffusion bonded to the end structure. Another embodiment of the lighting device has an arc envelope and an end structure diffusion bonded to an open end of the arc envelope.

Abstract: A discharge lamp has an electrode comprising a base portion having a base portion side flange portion, and a lid portion having a lid portion side flange portion. In a sealed space of the electrode, heat conductive member is enclosed. At time of lighting, the electrode is not damaged, and the discharge lamp can be stably operated. In the electrode, the diameter direction width of a welding portion of a base portion side flat portion and a lid portion side flat portion is 0.8 to 3.0. Further, an angle formed by the base portion side flat portion and a base side slope portion is 30 degrees or less and an angle formed by the lid portion side flat portion and a lid side slope portion is 30 degrees or less. The sum total of these angle is 160 degrees or less.

Abstract: A discharge lamp includes an airtight tube including a light-emitting unit in which a space is formed and seal portions formed at least on one end of the light-emitting unit, a discharge medium including a metal halide and a rare gas sealed in the light-emitting unit, a metal foil sealed into the seal portion, and a pair of electrodes one ends of which are overlapped and connected to the metal foil and the other ends of which are provided such that they are led into the space of the light-emitting unit and arranged in opposition to each other. A concavity is formed on at least a portion of the back surface side of the metal foil on which the electrode is overlapped, and a compression distortion is formed on the seal portion in the vicinity of the concavity.

Abstract: It is aimed at providing a metal halide lamp including sealed metal foils embedded within sealing portions, each metal foil having surfaces formed with height differences thereon, thereby restricting occurrence of crack leaks in the sealing portions.

Abstract: It is provided a dielectric barrier discharge lamp (10) for providing ultraviolet light, comprising an outer tube (12) filled with a discharge gas for providing ultraviolet light, an inner tube (14) arranged at least partially inside the outer tube (12), an outer electrode (16) electrically connected to the outer tube (12) and an inner electrode (18) electrically connected to the inner tube (14), wherein the inner electrode (18) comprises a conductor (20) and a plurality of an conductive granulated material (22) for providing an electrical contact between the conductor (20) and the inner tube (14). Due to the conductive granulated material (22) an electrical contact between the conductor (20) and the inner tube (14) is safeguarded and different thermal expansions of the inner electrode (18) and the inner tube (14) are compensated at the same time without applying mechanical stress to the inner tube (14).

Abstract: A high-intensity discharge lamp including an arc tube provided with a heat-resistant translucent discharge vessel forming a discharge space, an electrode structure, a discharge medium charged in the discharge vessel, the discharge medium being composed of a light-emitting metal including mercury and a starting gas, a support member electrically connected with the electrode structure of the arc tube and holding the arc tube and an outer bulb having the arc tube disposed therein along a tube axis and sealed with a support member at an end portion thereof. The electrode structure has an electrode shaft hermetically sealed at each of opposed end portions of the discharge vessel and having a tip portion disposed in the discharge vessel, a coiled electrode wound around the tip portion of the electrode shaft disposed in the discharge vessel, and a recessed portion or a protruding portion formed on the electrode shaft spaced from the coiled electrode.

Abstract: An electrode for an extra-high pressure discharge lamp, comprises large diameter portion which is symmetrical with respect to an axis of the electrode, a small diameter portion connected to the large diameter portion, wherein the large diameter portion is connected to the small diameter portion through an outer surface portion of the electrode, wherein a stripe lines like pattern portion, extending along an electrode axis direction, is formed on a portion to be brought in contact with glass of a lamp, and wherein unevenness is formed over an entire circumference of the electrode in a cross sectional view of the electrode taken along a direction perpendicular to the electrode axis direction.

Abstract: The present invention is directed to a method for manufacturing a high-pressure discharge lamp including: a spherical portion forming a light-emitting portion (1a); sealing portions that are connected with both ends of the spherical portion; an electrode (2a) that is sealed to each of the sealing portions; and a metal foil (3a) that is connected with a rear end of each electrode. A vessel provided with a cylindrical glass tube (8) on both ends of the spherical portion is used, a connection structure of the metal foil and the electrode are disposed in the glass tube such that a front end of the electrode is positioned in the spherical portion, and the glass tube is melted by heat and shrunk for sealing the metal foil and the electrode so as to form the sealing portion. An inner diameter ? of the glass tube before the heat-melt processing and a distance L from an edge of the metal foil to the internal space of the spherical portion are set to satisfy a relationship of L/??1.

Abstract: In a case of manufacturing a double ended discharge lamp, it is intended to decrease the manufacturing cost while maintaining identical lamp characteristic and lamp lifetime with those in a case of forming a quartz bulb with quartz at a high purity. In a quartz bulb (1) in which a pair of straight tube portions (2A, 2B) each having a sealing tube (4A, 4B) for sealing an electrode mount (M) and a supply/exhaust tube (5A, 5B) that is cut and removed after sealing in communication to each other are formed on both ends of a chamber (3) as a light emitting portion, end portions (1A, 1B) of the quartz tube including the entire portion or a portion of the supply/exhaust tubes (5A, 5B) are formed in contiguous with the central portion (10) of the quartz tube including all portions forming the inner surface (3a) of the chamber, and one or both of the end portions (1A, 1B) of the quartz tube is formed of quartz at a purity lower than that of the central portion (10) of the quartz tube.

Abstract: To provide a high pressure discharge lamp in which no fusing of the metal foil occurs even if the high pressure discharge lamp is switched on for a certain time a high pressure discharge lamp is provided having a discharge vessel comprised of a light emission part and sealing parts made of glass connected to opposite ends of said light emission part; metal foils buried in a respective one of said sealing parts; a pair of electrodes comprised of core rods and tip end parts, said tip end parts being arranged oppositely to each other in the light emission part; and said core rods being melted and fused together with a respective one of the metals foils; wherein cavities are formed which reach from a surface of a respective one of the metal foils to an interior of the core rod, and the glass constituting said sealing part has entered into said cavities.

Abstract: In a high pressure discharge lamp having electrode rods with grooves formed in a part thereof and embedded and sealed in sealing parts of a discharge vessel, breakage of the sealing parts because of the grooves is prevented without impairing the mechanical strength of the electrode rods, in which the grooves are formed, by the high pressure discharge lamp comprising: a discharge vessel having a light emitting part and sealing parts connected to both ends of said light emitting part; and electrodes comprising electrode rods and electrode tip end parts arranged oppositely to each other in the light emitting part, said electrode rods being embedded in a respective one of said sealing parts, and axially directed grooves being formed in at least part of the surface of said electrode rods, wherein a diameter measured at groove bottom parts of the grooves of said electrode rods is larger than a diameter of the electrode rods in a part where no grooves are formed.

Abstract: A high-pressure discharge lamp is provided. The high-pressure discharge lamp may include a ceramic discharge vessel, electrodes respectively being guided out of the discharge vessel by means of a leadthrough system via capillaries, wherein at least one leadthrough system is at least of tripartite form, including a first leadthrough part that is at the front with reference to the discharge, is corrosion resistant and is held entirely in the capillary, and a second, middle leadthrough part that is not corrosion resistant and is likewise held entirely in the capillary, there being adjacent thereto a third, rear, corrosion resistant leadthrough part, a soldering glass covering a segment of the first leadthrough part up to a segment of the third leadthrough part such that the soldering glass entirely covers the second, middle leadthrough part, the middle leadthrough part being sunk in the capillary to a depth of at least 0.1 mm.