Abstract: A high-pressure discharge lamp may include a quartz glass bulb which encloses a discharge volume, and a fill which contains mercury and noble gas as well as metal halides being held in the discharge volume, wherein the fill contains both dysprosium halides and also oxyhalides of at least one of tungsten and mercury based on at least one of the halogens bromine and chlorine.

Abstract: A high-pressure discharge lamp comprising an arc tube, the arc tube including: a light-emitting part which is substantially ellipsoidal; and sealing parts which extend from either end of the light-emitting part and in which bases of electrodes are sealed, the arc tube enclosing 0.2 mg/mm3 to 0.4 mg/mm3 of mercury, the high-pressure discharge lamp having a power rating greater than 355 W and not greater than 600 W, wherein 5.4?D?5.8 and 3.1?X?D?2.3 when 355<P?380, 5.8?D?6.2 and 3.1?X?D?2.7 when 380<P?450, and 6.2?D?6.6 and 3.1?X?D?3.3 when 450<P?600, where P denotes the power rating in watts of the high-pressure discharge lamp, D denotes an inside diameter in millimeters of the light-emitting part 104 with reference to a midpoint between the electrodes 101, and X denotes a wall thickness in millimeters of the light-emitting part 104 with reference to the midpoint between the electrodes 101.

Abstract: A lamp includes a discharge vessel with electrodes extending into the discharge vessel and an ionizable fill scaled within the vessel. The fill includes a buffer gas, optionally mercury, and a halide component. The lamp includes available oxygen, sealed within the discharge vessel, at a concentration of at least 0.1 ?mol O/cc.

Abstract: A high pressure discharge lamp of the present invention is provided with a light-emitting bulb comprising a light-emitting part and sealing sections; metal foils embedded within the sealing sections; and a pair of electrodes having one end protruding into the light-emitting part and having the other end embedded in the corresponding sealing section and joined to the corresponding metal foil. An embedded length L (mm) of the electrodes that is defined by the length between a light-emitting part side end of the metal foil and the border section between the protruding section and the embedded section of the electrode, and the temperature T (° C.) at the joint region of the electrode and the metal foil are set to satisfy 1.8?L?2.8 and T?970.

Abstract: An energy saving gas discharge lamp, and method of making same, is provided. The gas discharge lamp includes a light-transmissive envelope, and an electrode within the light-transmissive envelope to provide a discharge. A light scattering reflective layer is disposed on an inner surface of the light-transmissive envelope. A phosphor layer is coated on the light scattering reflective layer. A discharge-sustaining gaseous mixture is retained inside the light-transmissive envelope. The discharge-sustaining gaseous mixture includes more than 80% xenon, by volume, at a low pressure.

Abstract: A fluorescent lamp includes a tubular member or envelope having an arc generating and sustaining medium therein. An electrode is provided in each end of the tubular member and a phosphor coating is applied to the interior surface of the tubular member. A mercury dispenser is situated within the tubular member. The mercury dispenser includes a body composed of a material. The body is provided with a bore. A wire plated with a material capable of wetting mercury is provided in the bore. A quantity of mercury is deposited in the bore in contact with the wire.

Abstract: The present invention aims to provide a small-sized high-efficiency high pressure discharge lamp that exhibits favorable light intensity distribution properties and is less likely to cause breakage of an arc tube. The present invention is a high pressure discharge lamp 101 comprising: an arc tube 110 that includes; a light-emitting part 111 having a substantially spherical shape and having mercury enclosed therein; and a pair of sealing parts 112 extending from opposite sides of the light-emitting part 111; and a pair of electrodes 130 that are arranged in the arc tube 110 such that an end of each electrode is sealed by a respective sealing part and the other ends of the electrodes oppose each other in the light-emitting part. The enclosed mercury has a density of 0.2 to 0.4 [mg/mm3] inclusive. A distance W from a contact point S to a center O is 3.0 to 5.0 [mm] inclusive. A distance CO from a contact point TO to the center O is 1.5 to 3.0 [mm] inclusive.

Abstract: A high-pressure discharge lamp with an axial symmetry axis and metal halogenide filling has electrodes with shafts designed as pins with a diameter of 0.5 to 1.15 mm. The halogen for the halogenide is composed of iodine and possibly bromine components, iodine being used alone or in combination with bromine, and the bromine/iodine atomic ratio amounting to maximum 2.

Abstract: The invention relates to a high-pressure mercury discharge lamp for DC operation at a nominal wattage of more than 1.5 kW. Said high-pressure mercury discharge lamp comprises an anode, at least some areas of which are made of a material containing at least some tungsten, said material having a grain number of more than 200 grains per mm2 and a density of more than 19.05 g/cm3.

Abstract: In various embodiments, a high-pressure discharge lamp that is intended to operate with system voltage. The high-pressure discharge lamp may include a discharge vessel that surrounds a discharge volume, a fill that contains metal halides, mercury and inert gas from the group of neon, argon, krypton and xenon being accommodated in the discharge volume, wherein the fill contains at least one of the halogens of iodine and bromine, a zero current phase in the power supply being bridged by selecting the cold fill pressure of the inert gas in the range of 4 to 8 bar.

Abstract: The gas discharge lamp contains a lamp body and an UV unit. The UV unit contains a separate airtight chamber wrapping around at least a neck member of the lamp body and covering at least a part of a Mo tinsel inside the neck member. The airtight chamber is filled with one or more gases capable of being ionized, and is wound by a conductor whose one end is connected to a conduction wire extended out of one of the neck members. When the gas discharge lamp is turned on, the gases in the airtight chamber are ionized to produce an UV light to penetrate the discharge chamber. The gas discharge lamp therefore could have a lower starting voltage and an improved starting efficiency. Additionally, as the airtight chamber provides a heat insulation effect, the temperature-induced stress is thereby reduced.

Abstract: A fluorescent lamp (10) includes a tubular member or envelope (12) having an arc generating and sustaining medium (15) therein. As known, the tubular envelope (12) is constructed of a suitable glass, for example lime glass. An electrode (14) is provided in each end of the tubular member (12) and a phosphor coating (16) is applied to the interior surface (18) of the tubular member (12). A mercury dispenser (20) is situated within the tubular member (12). The mercury dispenser (20) includes a body (21) composed of a material selected from the group consisting of glass and ceramic materials. The body (21) is provided with a bore (22). A first material (24) capable of wetting mercury coats the bore. In a preferred embodiment the first material (24) is silver having a thickness between 0.1? and 8?. A quantity of mercury (26) is deposited in the bore (22) in contact with the first material (24).

Abstract: The invention relates to a high-pressure mercury discharge lamp for DC operation at a nominal wattage of more than 1.5 kW. Said high-pressure mercury discharge lamp comprises an anode, at least some areas of which are made of a material containing at least some tungsten, said material having a grain number of more than 200 grains per mm2 and a density of more than 19.05 g/cm3.

Abstract: A metal halide fill for forming an ionizable fill comprises at least one inert gas, mercury and metal halides, the fill comprising the constituents V halide, Cs halide, Tl halide and halides of the rare earths. This fill may in particular be contained in the discharge vessel of a metal halide lamp.

Abstract: A metal halide fill for forming an ionizable fill comprises at least one inert gas, mercury and metal halides, the fill comprising the constituents In halide, Na halide, Tl halide and halides of the rare earths. This fill may in particular be contained in the discharge vessel of a metal halide lamp.

Abstract: A lamp includes a discharge sustaining fill which includes cesium halide, one of indium halide and thallium halide, optionally gadolinium halide and a rare earth halide component selected from dysprosium halide, holmium halide, thulium halide, and neodymium halide. In operation without a jacket, the lamp may have a color temperature of from 7,000K to 14,000K and a color rendering index of at least 70 when operated at an arc wall loading in excess of about 2 W/mm2.

Abstract: A low wattage mercury vapor lamp comprises a discharge vessel (10) including a tubular body (12), first and second electrodes (20, 22) and two end walls (16, 18), which close opposite ends of the tubular body. The discharge vessel contains an ionizable fill material having a concentration of mercury of from 0.10 to 0.20 mg/mm3. The discharge vessel operates at elevated pressures of from 80 to 170 atmospheres at power of 20 watts resulting in improved lumen maintenance and reduced through-life color shift.

Abstract: A light source device for a projector device having a discharge lamp with a silica glass discharge vessel containing a pair of opposed electrodes and at least 0.15 mg/mm3 of mercury, a concave reflector which surrounds the discharge lamp and reflects light emitted from the discharge lamp in a given direction, and a power supply device which selectively supplies a first wattage and a lower second wattage, is provided with a reflection heating arrangement which, in operation of the discharge lamp with the lower second wattage, returns at least part of the light emitted by the discharge lamp in the direction of the discharge lamp, and in operation of the discharge lamp at the first, higher wattage returns less light than in operation with the second wattage in the direction of the discharge lamp.

Abstract: The invention relates to a blended light lamp (1) having an incandescent lamp (2) and a gas discharge lamp (3), a rectifier (4), an energy storage means (5) and an ignition device (6). The high-pressure discharge has an operating voltage of 180 V, which can be achieved by filling a discharge vessel of the gas discharge lamp (3) with, in particular, an amount of mercury of 153 micromole/cm3. In this way a high total luminous flux can be obtained in the operating state.

Abstract: A metal halide lamp (10) includes a discharge vessel (12) which may be formed of a ceramic material. The vessel defines an interior space (16). An ionizable fill is disposed in the interior space. The ionizable fill includes an inert gas and a halide component. The halide component includes a sodium halide, a cerium halide, at least one of a thallium halide and an indium halide, and optionally a cesium halide. The cerium halide is at least about 9 mol % of the halide component. At least one electrode (18, 20) is positioned within the discharge vessel so as to energize the fill when an electric current is applied thereto.

Abstract: The invention relates to a high pressure discharge lamp intended for use in assimilation lighting. According to the invention the high-pressure discharge lamp has a discharge vessel, which besides a buffer gas, comprises substantially LiI as metal halide or a mixture of LiI and NaI.

Abstract: An energy-saving assembly of an elongate low-pressure mercury vapor discharge lamp (1) and at least one elongate extension (2). The low-pressure mercury vapor discharge lamp includes a light-transmitting discharge vessel (10) enclosing, in a gastight manner, a discharge space (15) provided with a filling of mercury and a rare gas mixture. The rare gas mixture includes at least 50% by volume of krypton. The discharge vessel is provided with a luminescent layer (13). Electrodes (4a; 4b) are arranged in the discharge space for maintaining a discharge in the discharge space. The extensions are provided for connection to the low-pressure mercury vapor discharge lamp. The extension includes an inductance (3). The length of the low-pressure mercury vapor discharge lamp together with the length of the extension is adapted to fit a pre-determined mounting distance of tow-pressure mercury vapor discharge lamps.

Abstract: An object of the invention is to reduce the adverse effects due to a difference of thermal expansion between a conductive sealing member and a light-emitting vessel and to provide a reliable high pressure mercury lamp, even when the lamp is operated at a high pressure. The lamp has a light-emitting vessel 16 of quartz and having end portions, an electrode member 10 contained in the vessel 16, and a conductive sealing member 7A. The sealing member 7A is fixed in the end portion and connected to the electrode member 10. The conductive member is composed of a sintered body made from silica granules each having a coating of a metal or a metal compound. The sintered body has a conductive network structure made of the metal and having a content of the metal of not higher than 20 volume percent.

Abstract: A high-pressure discharge lamp has a lamp bulb of silica glass encapsulating mercury, an inactive gas, and a mixed halogen gas containing at least two halogen gases, and at least a pair of electrodes disposed in the lamp bulb in confronting relation to each other. The type and content of a primary halogen gas whose content is the greatest in the mixed halogen gas are determined based on a bulb wall load.

Abstract: It is an object of the present invention to provide a high pressure discharge lamp lighting apparatus, has a structure to control decrease of illuminance on a screen which is thought to be a cause of wear of an anode in an early stage of the life span. The high pressure discharge lamp lighting apparatus has a high pressure discharge lamp in which a pair of electrodes is arranged so as to face each other at an interval of 2 mm or less in an arc tube which is made of quartz glass, and mercury of 0.16 mg/mm3 or more, rare gas, and halogen of 1×10?6 to 1×10?2 ?mol/mm3 is enclosed, and a power supply apparatus supplying direct current to the discharge lamp, wherein the power supply apparatus superimposes an alternating component on the direct current and impress the superimposed current to the discharge lamp.

Abstract: An electrodeless discharge lamp has a magnetic core 3, an induction coil 5, and a fixation member 7. The fixation member 7 has an elongation portion 7b extending in a direction along an axial line of the magnetic core 3, a holding portion 7c for holding the magnetic core 3 positioned closer to the magnetic core 3 than the elongation portion 7b, and hook portions 7d and 7e to which a winding wire 7 is hooked so as to be inflected. The hook portions 7d and 7e positioned away from a boundary between the holding portion 7c and magnetic core 3 toward the elongation portion 7b by a distance between once and twice of a diameter of the winding wire.

Abstract: A method for inhibiting mercury from leaching from a land-filled arc discharge lamp containing a quantity of elemental mercury at least partially convertible to soluble mercury, provides for including within the lamp a quantity of a non-metallic copper-containing compound and an ingredient X, said ingredient X including a noble metal or a noble metal compound selected from the group consisting of silver and compounds of silver, gold and platinum, and a lamp containing same. The inhibiting compound is preferably included with the basing cement.

Abstract: Described is a high intensity discharge lamp including a lamp bulb envelope, first and second electrodes, a seal and a fill situated within the lamp bulb envelope. The lamp bulb envelope is composed of single crystal sapphire tubing. The lamp bulb envelope includes end portions and a central portion, the central portion having a greater diameter than the end portions. The end portions may be a cylindrical tube shape and the central portion is a smooth three-dimensional shape. The first and second electrodes extend through opposite ends of the lamp bulb envelope so that at least a portion of each of the electrodes is situated within the lamp bulb envelope. The seal seals each of the first and second electrodes to an inside wall of the corresponding end of the lamp bulb envelope. A voltage is applied to the first and second electrodes to generate an arc plasma therebetween.

Abstract: A long-life high-pressure discharge lamp suffers reduced blackening and luminance drop even after it has been turned on over a long period of time, and is arranged to prevent the internal gases from leaking out and also to prevent the lamp bulb from being ruptured. The high-pressure discharge lamp has a pair of confronting electrodes inserted in a lamp bulb which confines therein at least mercury and a halogen gas. The lamp bulb contains oxygen at a partial pressure lower than a partial pressure which can maintain a luminance of 80% after 100 hours of operation and equal to or higher than 1.0×10?5 Pa.

Abstract: An arrangement with a relatively high pressure tightness in a super-high pressure mercury lamp which is operated with an extremely high mercury vapor pressure is achieved in accordance with the invention in a super-high pressure discharge lamp of the short arc type having a light emitting part in which a pair of electrodes are disposed opposite each other and which is filled with at least 0.15 mg/mm3 mercury; and side tube parts which extend from each side of the light emitting part and in each of which a respective one of the electrodes is partially hermetically sealed and is connected to a metal foil, by the area of the respective metal foil which is connected to the respective electrode has a smaller width than the width in the remaining area of the metal foil, the area with the smaller width wrapping at least partially around the outside surface of the electrode.

Abstract: An arc lamp assembly which includes in combination a reflector and a light source which is surrounded by said reflector. A dichroic coating on the reflector functions to reflect radiation in the range of about 300 to 600 nm. The light source is an arc lamp which contains a metal halide fill component which includes a mixture of scandium iodide, or other suitable lanthanide, indium iodide and cesium iodide, whereby the lamp assembly emits effective amounts of UV radiation to cure selected chemical compositions. The fill mixture, which contains no sodium component, contributes to improved lamp life and a reduction in passive lamp failure over halide fill mixtures which contain sodium iodide as a fill component.

Abstract: An arrangement with relatively high pressure tightness in a super-high pressure mercury lamp of the short arc type which is operated with an extremely high mercury vapor pressure is achieved by the super-high pressure mercury lamp having the following characteristic: an arc tube portion in which there is a pair of opposed electrodes, and which is filled with greater than or equal to 0.15 mg/mm3 of mercury; and side tube portions which extend from opposite sides of the arc tube portion, in which the electrodes are partially hermetically enclosed, and in which the electrodes and metal foils are welded to one another, and the width of the metal foils in the weld areas is so small that it is less than or equal to the diameter of these electrodes.

Abstract: An ultra-high pressure mercury lamp in which both devitrification and also breakage of the discharge vessel can be eliminated. In the ultra-high pressure mercury lamp, there is a pair of opposed electrodes in a fused silica glass discharge vessel filled at least 0.15 mg/mm3 mercury, and an alkali metal concentration in the area from the inside surface of this discharge vessel to a depth of 4 microns that is at most 10 wt. ppm.

Abstract: Arc tube (10) has a bulbous body (12) with a hollow center portion (14) and opposite ends (16, 18). Each of these ends has a cylindrical terminal-receiving section (20, 22) extending therefrom. The hollow center portion (14) has an internal length A and an internal diameter B that provides an aspect ratio of less than 5 and an outer surface area to inner surface area ratio, measured in square units, of less than 1.5. Electrodes (24) and (26) are hermetically sealed in the terminal-receiving sections (20, 22). The lamp uses less than 7 mgs of mercury. The low pressure operation allows the use of the arc tube in lamps without a shroud and the low mercury allow the lamp to pass TCLP requirement and be conventionally landfilled.

Abstract: A metal halide lamp for an automobile headlight is provided, which includes an arc tube in which a pair of tungsten electrodes are provided at both ends and a metal halide as a main component of a luminescent material and xenon gas as a buffer gas are sealed, wherein the tungsten electrodes contain not more than 0.4 wt % of thorium oxide, the metal halide contains scandium iodide, and a pressure of the xenon sealed in the arc tube is at least 0.4 MPa. This makes it possible to provide a long-life metal halide lamp for an automobile headlight that can achieve a further improved lumen maintenance factor and other life characteristics during 2000 hours or more of lighting.

Abstract: An emission device for an ultra-high pressure mercury lamp which maintains an electrode tip shape by which a stable discharge can always be carried out is achieved for a short arc ultra-high pressure mercury lamp with silica glass arc tube containing a pair of opposed electrodes spaced apart a distance of at most 2 mm and in which the arc tube is filled with at least 0.15 mg/mm3 of mercury, a rare gas and a halogen in the range from 1×10−6 &mgr;mole/mm3 to 1×10−2 &mgr;mole/mm3; by providing an operating device which produces a current feed by which the surface of the tip of at least one of the electrodes is shifted into a molten state during lamp operation.

Abstract: A metal halide lamp comprised of a ceramic discharge chamber containing an ionizable fill, said fill comprising Hg, and halides (H) of Na, TI, an alkaline earth metal, and 0>rare earth element (Re)<15 as a molar fraction.

Abstract: The invention provides an arc tube with improved chromaticity and start-up characteristics that does not contain mercury, and provides a vehicle headlamp equipped with a metal halide lamp that contains no mercury in the arc tube. Among other improvements, the evaporation of low melting point metal halides is promoted and the start-up characteristics of the arc tube are improved.

Abstract: A short arc mercury discharge lamp including an arc tube filled with at least mercury and a rare gas, a cathode and an anode positioned opposite to each other within the arc tube, the cathode having an tapered area which tapers in a direction towards the anode and a projection which protrudes from the tapered area in a direction towards the anode. The amount of mercury to be added in the arc tube is in a range of 0.2≦n≦52, where n is the weight (mg/cm3) of the mercury per unit of volume, and a pressure of the rare gas to be added in the arc tube is in a range of 0.1≦p≦800, where p is the pressure (kPa) of the rare gas at an ambient temperature of 25° C.

Abstract: A super-high pressure discharge lamp of the short arc type which has an arc tube portion in which there is a pair of opposed electrodes and which is filled with at least 0.15 mg/mm3 mercury, and side tube portions which extend from opposite sides of the arc tube portion and in which there are metal foils. The electrodes are each electrically connected to a respective one of the metal foils by a metallic component with cross-sectional area that is smaller than the cross sectional area of the electrodes in the area in which the electrodes are located in the side tube portions.

Abstract: Discharge lamp includes a synthetic quartz glass tube having an inside diameter of 8 mm or over and a pair of filaments provided within and at opposite ends of the glass tube with an L (cm) filament-to-filament distance, and rare gas and metal including at least mercury are sealed in the interior of the glass tube. Lamp voltage V (V) and lamp current I (A) during illumination of the discharge lamp, filament-to-filament distance L (cm) and inside diameter D (cm) of the glass tube have relationship represented by the following mathematical expression. Namely, (V−Vf)/L=X/({square root over ( )}D·{square root over ( )}I) and 2.6≦X≦4.2, where Vf is a constant factor depending solely on a illuminating power source and where that if the discharge lamp is illuminated by a high-frequency power source of 1 kHz or over, Vf is 10, but if the discharge lamp is illuminated by a power source of 1 kHz or below, Vf is 50.

Abstract: A high pressure sodium lamp (100) having an evacuated glass envelope (6) with a plurality of electrically conductive support members therein and extending therethrough. An elongated arc tube (14) having a pair of electrodes (26) extending therethrough is affixed to the electrically conductive support members within the glass envelope. A gas fill includes a quantity of mercury and sodium within the elongated tube. The arc tube is selected from a translucent material that, when the lamp is operating, will have a wall temperature of about 1250 degrees Celsius, a wall loading of from about 18.9 to about 22.2 w/cm sqr., and a power consumption of from 150 to 400 watts. Further, the amount of mercury is reduced from 14.4 mgs/arc tube to 10.8 mgs/arc tube, allowing lamps having power consumption from 150 to 400 watts to pass the Toxicity Characteristics Leaching Procedure (TCLP).

Abstract: A high pressure discharge lamp includes a quartz glass bulb having an expanded portion and sealing portions, conductive elements, and a pair of electrodes. The conductive elements are sealed at the sealing portions of the quartz glass bulb. Each electrode is disposed so as to be opposite the other and connected to one conductive element. The lamp is characterized in that Dp (the distance between an end of each electrode) is in the range between 1.0 and 1.6 mm, S (the longest length of the expanded portion in the direction of a discharge path)=e×Di (wherein 0.8<e<1.0), Di (the largest inside diameter of the expanded portion transverse to the discharge path)=g×Dp (wherein 4<g<8 ), and Do (the largest outside diameter of the expanded portion transverse to the discharge path)<Di+4 mm.

Abstract: An ultra-high pressure mercury lamp in which both devitrification and also breakage of the discharge vessel can be eliminated. In the ultra-high pressure mercury lamp, there is a pair of opposed electrodes in a fused silica glass discharge vessel filled at least 0.15 mg/mm3 mercury, and an alkali metal concentration in the area from the inside surface of this discharge vessel to a depth of 4 microns that is at most 10 wt.ppm.

Abstract: An apparatus and method for obtaining short-term color stability in an HID lamp, the apparatus comprising in a first embodiment a high intensity discharge lamp with a discharge vessel and electrodes; with a filling within the discharge vessel containing a metal halide dose of at least 20 mg/cc, where volume is defined as the volume of the main cylindrical section of the discharge vessel. In a preferred embodiment, the filling within the discharge vessel contains Hg of at least 20 mg/cc, where volume is defined as the volume of the main cylindrical section of the discharge vessel. In a yet further aspect, the resulting color temperature is stabilized independent of the shape and frequency of the current and voltage waveforms that drive the HID lamp.

Abstract: The invention relates to a method of adjusting a desired spectrum of light emitted by a gas discharge lamp during its operation, said gas discharge lamp comprising a first ionizable substance and a second substance which is less readily ionizable than the first substance. According to the invention, the gas discharge lamp is operated such that gases of both substances cans be excited, while the partial pressure of the first substance is adjusted in dependence on the desired spectrum. For this purpose, for example, the current through the lamp may be modulated. In an alternative embodiment, this is suitably achieved in that the partial mercury pressure is varied, for example through an adjustment of the temperature of a mercury amalgam present in the gas discharge lamp. The invention also relates to a gas discharge lamp whose color can be varied during its operation, and to a luminaire provided with a supply for such a lamp.

Abstract: A glow starter comprises a discharge vessel, filled with a filling including a rare gas, substantially transmitting ultraviolet rays of about 300 nm or less. A pair of electrodes, which are arranged in the discharge vessel, is adapted and arranged to touch each other by being heated by a glow discharge. The glow starter may be used for a high pressure discharge lamp, a high pressure discharge lamp apparatus, or a lighting fixture.

Abstract: The present invention provides a short arc type mercury discharge lamp that, at lamp startup time, quickly shifts glow discharge to arc discharge, and quickly shifts the arc discharge position from the coil to the electrode tip, making it possible to maintain a stable discharge state, in the short arc type mercury discharge lamp 1, a coil 5 has been arranged on the side surface of an electrode 4, and 0.15 mg/mm3 or more of mercury has been sealed inside a discharge vessel, wherein the side part 51 of the coil 5 close to the tip side of the electrode is constructed so as to be fixed to the side surface of the electrode 4, and, at least, the part 52 of the coil 5 following the side part 52 is distanced from the side surface of the electrode.

Abstract: The present invention provides a high pressure discharge lamp which is provided with a discharge tube containing a pair of electrodes therein and being filled with mercury, an inert gas and a halogen gas, the amount of the mercury filled being 0.12 to 0.35 mg/mm3, the halogen gas being at least one gas selected from the group consisting of Cl, Br and I and being present in an amount of 10?7 to 10?2 ?mol/mm3, and the electrodes being mainly composed of tungsten, and the tungsten as a material of the electrodes contains not more than 12 ppm of potassium oxide (K2O). In such a high pressure discharge lamp, blackening of the discharge tube due to the potassium oxide (K2O) contained in the tungsten, and decrease in illumination maintenance can be prevented, thus providing a high pressure discharge lamp with a long lifetime, a lighting optical apparatus using the high pressure discharge lamp as a light source, and an image display system using the lighting optical apparatus.

Abstract: An arc lamp assembly which includes in combination a reflector and a light source which is surrounded by said reflector. A dichroic coating on the reflector functions to reflect radiation in the range of about 300 to 600 nm. The light source is an arc lamp which contains a metal halide fill component which includes a mixture of scandium iodide, or other suitable lanthanide, indium iodide and cesium iodide, whereby the lamp assembly emits effective amounts of UV radiation to cure selected chemical compositions. The fill mixture, which contains no sodium component, contributes to improved lamp life and a reduction in passive lamp failure over halide fill mixtures which contain sodium iodide as a fill component.