Abstract: A low watt metal halide discharge lamp for use in photo-curing photo-curable compositions. The lamp comprises an envelope made of light transmissive material having walls that define an arc chamber volume. Contained within the arc chamber volume is a fill of mercury, inert gas and a metal halide additive that includes indium iodide or indium triiodide. The mercury and metal halide are adapted to substantially vaporize during operation of the lamp and produce radiant energy substantially within the wavelength range between about 400 and 500 nm. Extending into the arc chamber volume is a pair of electrodes having electrode tips spaced apart from one another by a predetermined distance. The lamp also includes a pair of inlead assemblies electrically coupled to a pair of electrodes respectively. The inlead assemblies pass from the electrodes through a sealed section to the exterior of the lamp.

Abstract: A light mirror and a lamp including a light mirror are disclosed. The light mirror includes a light pervious substrate having a reflecting surface, a metal coating disposed in the reflecting surface, and a dichroic coating disposed on the metal coating. The dichroic coating is designed to reflect essentially all of the visible light spectrum and to transmit infra-red radiation and any unreflected portion of the visible light spectrum. A method for controlling the heat transmission of a cold light mirror is also disclosed.

Abstract: Two series connected high pressure sodium arc discharge tubes include a saturated arc tube and an unsaturated arc tube. When the saturated arc tube voltage shifts in value due to changes in operating conditions, the other unsaturated arc tube voltage does not shift to compensate for the voltage increase. Because the unsaturated arc tube voltage does not shift, the rate of voltage shift of the saturated arc tube is smaller in magnitude than otherwise would occur if both arc tubes were saturated.

Abstract: An electrodeless high pressure discharge lamp contains a halide or oxyhalide of W, Ta, Re, or rhenium oxide in such a quantity that a supersaturated metal vapor arises in the discharge, by which metal particles are formed. Owing to their high temperature these particles generate thermal emission. The lamp has a high color temperature and a high color rendering index.

Abstract: A metal vapor discharge lamp comprises a light-emitting tube filled with bismuth together with mercury, a rare gas, iron and a halogen in the range of 1/20-6/1 in terms of the gram atom ratio of bismuth to iron (Bi/Fe). A metal vapor discharge lamp also comprises a long light-emitting tube having an inner diameter D of 18-35 mm, equipped with a pair of electrodes and having an electrode interval L of 750 mm or greater, filled with bismuth together with mercury in a sealed amount of 0.6-2.0 mg per cc of the internal volume of the light-emitting tube, a rare gas, iron and a halogen in the range of 1/20-6/1 in terms of the gram atom ratio of bismuth to iron (Bi/Fe).

Abstract: An electrodeless discharge tube containing a fill which comprises a metal carbonyl complex. Such a complex will be sufficiently volatile to produce a vapor pressure in a discharge tube in which a discharge can be generated. The discharge so generated emits a mixture of visible and infra-red radiation.

Abstract: A protective beryllium oxide coating of suitable thickness is applied to the inner surface of the arc tube of a high-intensity, metal halide discharge lamp in order to avoid a substantial loss of the metallic portion of the metal halide fill and hence a substantial buildup of free halogen, thereby extending the useful life of the lamp. A preferred lamp structure includes a fused silica arc tube. The beryllium oxide coating is preferably applied to the arc tube by evaporating beryllium in the arc tube under non-oxidizing conditions, and then heating in an oxidizing atmosphere.

Abstract: Disclosed herein is a lighting lamp having a light-emitting tube in which lutetium (Lu), lithium (Li) and a halogen are sealed together with mercury and a rare gas. The lighting lamp satisfies the following conditions (1) and (2):(1) the proportion Li/Lu (the ratio in terms of the number of atoms of lithium to lutetium) is 0.5 to 1.5; and(2) the sealed amount of the halogen is the total of a stoichiometric amount of halogen in which the halogen form halides with lutetium and lithium to be sealed and an excess amount of 0.5.times.10.sup.-6 to 4.times.10.sup.-6 molecular mole/cc based on the internal volume of the light-emitting tube.

Abstract: A negative glow discharge lamp including a light transmitting envelope having supported therein electrode means for establishing a negative glow discharge in the lamp. The fill material includes a metal-based gas such as sodium which, upon excitation thereof, directly emits visible light. The sodium has a resonance radiation in the visible part of the spectrum. The cathode is a hot cathode.

Abstract: Metal halide vapor arc lamps for reprographic and projection processes emitting in the blue, green and red bands with excellent primary color separation and having significant blue emission at a wavelength of about 450 nm, contain a fill of indium, zinc, lithium and thallium iodides.

Abstract: Improved efficacy and color rendition are achieved in a high intensity discharge, solenoidal electric field (HID-SEF) lamp by using a novel combination of fill ingredients, including lanthanum halide, sodium halide, cerium halide, and xenon or krypton as a buffer gas. The preferred lamp structure is that of a short cylinder having rounded edges in order to achieve isothermal lamp operation and further efficacy improvement.

Abstract: A high-pressure sodium vapor lamp with elevated color temperature, high light yield and improved color rendering properties for general illumination purposes uses sodium or sodium amalgam with mole fractions x.sub.Na >0.9 as the arc media. The lamp power supply supplies pulses with a duty cycle .GAMMA.of 0.01>.GAMMA.>0.1 with alternating polarity, or with mole fractions x.sub.Na >0.95 even at uniform polarity, respectively.

Abstract: A high pressure sodium lamp including a light permeable arc tube and an electrode extending into the arc tube via a central aperture provided in the arc tube. The electrode is supported in the aperture by means of a glass solder sealing composition. Sodium amalgam is seated in the arc tube and condensed at a corner thereof. To prevent sodium amalgam condensed at the corner of the arc tube from contacting the glass solder filled in the central aperture of the arc tube, sodium amalgam including sodium of 10-30 (wt %) is sealed in the arc tube at a prescribed volume V (mm.sup.3) which substantially satisfies the following relationship: ##EQU1## where D (mm) is the diameter of the arc tube, d (mm) is the diameter of the central aperture, Vo (mm.sup.3) is the volume of the sodium amalgam sealed in the arc tube when the shortest distance between the sodium amalgam condensed at the corner and the glass solder filled in the central aperture is given by ##EQU2## and WL (W) is the lamp power.

Abstract: A fluorescent light source based on a phosphor excited by a molecular discharge is described. The fluorescent light source comprises a capacitively coupled compact fluorescent lamp coated with a manganese doped magnesium aluminate phosphor on the inside surface of the lamp envelope. The compact fluorscent lamp produces a plasma which emits 206 nm radiation from the molecular discharge of the iodine containing molecular vapors and inert gas fill which in turn excites the phosphor to emit visible light.

Abstract: The high-pressure gas discharge lamp has an ovoidal discharge space with oppositely arranged rod electrodes having a electrode coils spaced from the tip ends of the electrode. The ratio between the electrode distance d and the largest diameter of the discharge space D lies between 0.75 and 1.25. The lamp has a comparatively high power of 1600-2000 W and a defined Br/I ratio of 1.5-4. When arranged transversely in a luminaire having a concave rotation-symmetrical reflector and a screen, the lamp produces an accurately defined light beam suitable for illumination of sports grounds.

Abstract: The invention relates to an unsaturated high-pressure sodium lamp provided with a discharge vessel enclosing a discharge space, having a ceramic wall and closed at both ends by a leadthrough element to which an electrode is secured, and at least one electrode provided with emitter material. The fill material within the discharge vessel contains sodium, mercury and a rare gas. According to the invention, the discharge space also contains in metallic form one or more of the elements Mg, Ca, Sr and Ba up to at most 10% by weight of the mercury metered.

Abstract: A high intensity discharge electrodeless lamp having a segmented excitation coil and capacitor configuration offers minimum light obstruction and RF losses while providing maximum impedance matching and heat transfer from the coil to a heat sink. The excitation coil includes at least two pairs of interconnected windings, each pair disposed concentrically in its own plane. The windings are clustered in a toroidal shape, the center of which is positioned to surround the arc envelope of a high intensity discharge lamp containing an ionizable gas activatable by RF energy. The coil windings are of large cross-sectional area and the capacitors have short leads, so as to minimize EMI and power losses and facilitate heat condition to heat sink means. The windings are configured to follow the contours of the magnetic field lines created by current flow through the total coil.

Abstract: Disclosed is a low-pressure discharge lamp comprising a discharge vessel defining an airtight space therein, at least one pair of electrodes disposed in the discharge vessel, and discharge gases enclosed in the discharge vessel, one of the electrodes which acts as an anode being located in a zone of negative glow.

Abstract: An improved optical radiation source for use in illumination that is obtained from a thinwall tubular arc lamp with a high input power density that delivers high brightness. It includes a constricting enclosure that exerts a compressive force upon the insulating tube forming the envelope of said lamp to counteract tensile strain in the tube caused by higher gas pressure within the tube and a higher thermal gradient within the walls of said tube.

Abstract: A rapid restrike metal halide lamp and method of operating such a lamp are disclosed which are particularly suitable for sports stadium lighting applications. The rapid restrike metal halide lamp has an arc tube containing constituents which require a waveform having a relatively high voltage and at a relatively high current in order to rapidly restrike the arc tube after the lamp has experienced a power interruption so as to initiate a sustaining arc condition of the arc tube. The relatively high waveform in the form of a series of pulse trains is routed to the arc tube by means of a two path arrangement comprising a conductive base at the bottom of the lamp and a insulative cap at the top of the lamp. This two-way path substantially reduces and even eliminates any arcing condition within the confines of the lamp.

Abstract: A metal vapor discharge lamp has a luminous tube constituted by a translucent ceramic tube member, end caps hermetically fixed to both ends of the translucent ceramic tube member, and electrode supporting tubes hermetically inserted into respective end caps. One of the electrode supporting tubes serves also as an exhaust tube for evacuation and also as a reservoir for a metal charged in the luminous tube. The outer end extremity of this electrode supporting tube is hermetically sealed through fusion by application of heat. This hermetic seal is formed by fusing the end of the electrode supporting tube by application of heat thereto, while keeping a heat-shielding/absorbing plate held in close contact with the electrode supporting tube.

Abstract: A metal vapor discharge lamp. The metal vapor discharge lamp includes an enclosed discharge tube having a pair of main electrodes mounted at spaced apart locations therein, the discharge tube including a fill of at least a metal vapor and a starting gas, a radiation source including radioactively impregnated ceramic material having a vitrified radioactive outer protection portion and an outer bulb for enclosing the discharge tube and a circuit for electrically generating an arc between the main electrodes.

Abstract: A metal halide discharge lamp for use in plant growing is disclosed. The lamp of the present invention includes an outer envelope having an inner surface, the inner surface including thereon a phosphor layer, the phosphor being selected to convert ultraviolet wavelength radiation into radiation having a wavelength from about 710 to about 780 nanometers; and a silica quartz shaped arc tube with central part being expanded including therein a pair of spaced electrodes and a chemical fill, the chemical fill comprising mercury, an inert gas, indium halide, lithium halide, sodium halide, and cesium halide. A preferred phosphor comprises iron-doped lithium aluminate. A most preferred chemical fill includes indium iodide, lithium iodide, sodium iodide, and cesium iodide in a molar ratio 0.6 to 7.4 to 1.3 to 0.4, respectively, mercury, and an inert gas.

Abstract: A metal-halide arc tube and lamp having improved uniformity of azimuthal luminous intensity and being particularly suited for navigational signal applications. The arc tube when operationally positioned about a vertical axis has a body which is substantially egg-shaped with the lower half of the body being more oblate than the upper half. During operation, the surface of the upper half of the arc tube body remains entirely free of metal-halide condensate so that no emitted light is blocked by condensate in any direction and nearly uniform azimuthal intensity is achieved. A heat-reflecting coating about the lower electrode prevents the formation of a condensate puddle about the lower electrode and relocates the condensate during operation to an area of the lower half above the coating and below the center of the arc tube.

Abstract: Improved efficacy and color rendition at white color temperatures is achieved in an electrodeless metal halide arc discharge lamp with a novel combination of arc tube fill materials, including sodium halide, cerium halide, and xenon. A preferred lamp structural configuration imparts further efficacy improvement at higher lamp operating temperatures and isothermal lamp operation.

Abstract: A phosphor comprises a chromium activated alkaline earth aluminate having a hexagonal crystal structure and incorporates divalent europium as a sensitizer. The phosphor may also incorporate one or more of divalent manganese and/or zinc and/or magnesium. Such a phosphor emits in the infra-red.

Abstract: In an arc tube for a high intensity metal halide discharge lamp, a particular composition of metal halide dose is provided to control thorium transport to the electrodes within the arc tube and tungsten transport to the wall to improve arc tube performance.

Abstract: High pressure xenon is used as a buffer gas in an electrodeless sodium iodide arc lamp. Very high efficacies are achieved by using an arc tube with rounded edges and by surrounding a portion of the arc tube with quartz wool. The arc tube may also contain small amounts of mercury iodide.

Abstract: A metal vapor discharge lamp includes a light-emitting tubing in which a halogen and iron at least 0.005 mg per cc of the internal volume of the light-emitting tubing are filled together with mercury and a rare gas in amounts sufficient to retain a discharge. Magnesium is additionally filled in at a magnesium-to-iron ratio of 1/40-2/3 in terms of gram atom number so as to prevent iron from depositing on the inner wall of the light-emitting tubing and forming a thin film thereon.

Abstract: An electric arc discharge switch having less susceptibility to electrode erosion and capable of being optically triggered. In a first embodiment the switch includes a gas tight body defining a hollow interior with electrodes mounted onto the body and forming a conducting path into the body interior. Portions of the body are optically transmissive to light frequencies above the photoelectric effect cutoff frequency for cesium vapor. A buffer gas and a predetermined quantity of vaporizable cesium are disposed within the hollow body interior and a flash lamp may be mounted onto the switch exterior. In operation, light frequencies above the photoelectric effect cutoff frequency for cesium are introduced into the switch body, ionizing the cesium vapor therein and reducing the resistance and breakdown voltage between the electrodes so as to initiate an electric arc. In an alternative embodiment a control plate with an aperture is disposed within the switch body between the electrodes.

Abstract: High pressure xenon is used as a buffer gas in place of mercury in a high pressure sodium iodide arc discharge lamp. Xenon buffer gas has a more favorable influence than mercury on the sodium D-line spectrum and does not react with halides in the lamp fill. The use of xenon buffer gas increases the efficacy of the high pressure sodium iodide arc lamp.

Abstract: A metal halide lamp provides exceptional color rendition because of a high calcium iodide partial pressure. A long-arc ellipsoidal arc tube provides a high "cold spot" temperature. The method of manufacture of the lamp includes heating the arc tube tubulation while burning the lamp after dosing, and then an evacuation step to eliminate moisture due to the hygroscopic calcium iodide.

Abstract: A fluorescent lamp is described in which spontaneous excimer UV emission in an inner tube results from reacting an inert gas molecule with a halide molecule in the excited state. The UV emission travels through the inner tube envelope to an outer tube and is absorbed by a fluorescent material, i.e., phosphor, to produce visible light which passes through the outer tube envelope. The halide may be supplied by metal halide pellets or liquid droplets, which when heated by an initial discharge through an inert gas, produces metal halide vapors which dissociate and combine with the inert gas (Xe, Ar, Ne, Kr) in the excited state and result in UV excimer emission.

Abstract: A low wattage metal halide discharge lamp includes a sealed outer envelope with a pair of electrical conductors passing therethrough and containing an arc tube having a pair of electrodes electrically connected to the pair of electrical conductors with a chemical fill within the arc tube including iodides of sodium and scandium of a molar ratio in the range of about 20:1 to 28:1.

Abstract: An arc discharge lamp is provided using sealing compositions comprising mainly Al.sub.2 O.sub.3 --SiO.sub.2 --MgO. Preferred compositions include between 25 to 28% by weight of MgO and 13 to 21% by weight of Al.sub.2 O.sub.3 since these have lower melting points than others in the group. The sealing compositions are used to seal end closure members of alumina or cermet to ceramic arc tubes for use in discharge lamps. The compositions are selected to have linear expansion co-efficients compatible with the materials of the end closures and arc tubes. The methods described give sealing times of between 3 and 4 minutes.

Abstract: A compact fluorescent lamp has an outer envelope in which there is supported a capsule containing a mercury-free fill comprised of aluminum tribromide. The fill is energized to produce a plasma discharge which emits ultraviolet and visible radiation. Phosphor, in the form of a particulate layer or a gas, converts the ultraviolet into visible light. The lamp may contain electrodes or be electrodeless. In the electrodeless embodiment RF energy may be capacitively or inductively coupled to the fill.

Abstract: An arrangement including a frequency converter (4) and a discharge lamp (10) connected thereto wherein the frequency converter (4) is of a type whose output frequency is at least 80 kHz, while the lamp is a low-pressure sodium vapor discharge lamp. This lamp supply system provides a high luminous efficacy for the lamp.

Abstract: An ultraviolet light source includes a volume filled with a dose of AlBr.sub.3 and an inert gas. No mercury is used. During electrical discharge excited states of AlBr.sub.2, and AlBr emit light, with AlBr having a broad ultraviolet emission peaking at about 278 nm. The source may be energized with or without internal electrodes. Phosphors may be employed to convert the ultraviolet to visible light. The lamp's envelope may be aluminosilicate coated quartz.

Abstract: A low wattage metal halide discharge lamp includes an evacuated envelope wherein is disposed a heat reducing member having an arc tube therein. The heat reducing member and the arc tube have a metal band and outer strap member adjacent one another and adjacent an electrode with the metal band, strap member and electrode all electrically connected to an electrical lead of one polarity whereby sodium losses from the arc tube are reduced.

Abstract: A low wattage metal halide discharge lamp includes an evacuated envelope wherein is disposed a heat reducing member having an arc tube therein. The heat reducing member and the arc tube have a metal band an outer strap member adjacent one another and adjacent an electrode with the metal band, strap member and electrode all electrically connected to an electrical lead of one polarity whereby sodium losses from the arc tube are reduced. Importantly, the evacuated envelope includes a getter and the heat reducing member is in the form of a domed sleeve having an open end directed away from the getters.

Abstract: Iodine in excess of sodium-iodide stoichiometry is used in the fill for a sodium iodide arc lamp which also includes sodium iodide and xenon buffer gas. The presence of free sodium near the arc tube walls is eliminated and efficacy is improved.

Abstract: Halides of aluminum or tin, or other metals, in combination with sodium chloride in the presence of mercury and excess aluminum or tin metal are used as a fill material in a solenoidal metal halide arc lamp. This fill results in very good color and a high efficacy.

Abstract: A low-pressure alkali metal vapor discharge lamp has a getter for bi- and triatomic gases and a getter holder in the arc tube near at least one electrode. The electrodes need be heated less strongly during evacuation of the prior to final dosing, as a result of which no emitter material of the electrodes is lost. The ignition voltage is considerably lower than that of conventional lamps without a getter.

Abstract: An arc discharge lamp is provided using sealing compositions comprising mainly Al.sub.2 O.sub.3 --SiO.sub.2 --MgO. Preferred compositions include between 25 to 28% by weight of MgO and 13 to 21% by weight of Al.sub.2 O.sub.3 since these have lower melting points than others in the group. Additives of B.sub.2 O.sub.3, nucleating agents and HfO.sub.2 and other rare earth oxides are preferred. The sealing compositions are used to seal end closure members of alumina or CERMET to ceramic arc tubes for use in discharge lamps. The compositions are selected to have linear expansion co-efficients compatible with the materials of the end closures and arc tubes. The methods described give scaling times of between 3 and 4 minutes.

Abstract: A high pressure metal vapor discharge lamp including an arc tube having at least a main electrode at each end thereof, a fill sealed in the arc tube, including mercury, metal halide and starting gases selected from the group consisting of Ar, Kr and Xe, a radioactive source material, impregnated with a radioactive substance having a half-life less than 1.times.10.sup.4 years, sealed in the arc tube and a circuit including a conventional low voltage mercury lamp ballast and a glow starter for starting the arc tube.

Abstract: A single-ended metal halide discharge lamp includes a plurality of fill gases selected to provide essentially white light at a plurality of distances from a pair of spaced electrodes and to combine the radiation from the multiple distances to provide white light with minimal color separation from the discharge lamp. Also, a method for providing spectral uniformity from a discharge lamp is provided wherein the emitted color and distance from a longitudinal axis provided by a plurality of fill gases is observed, fill gases are selected to provide white light emission at a plurality of distances from the longitudinal axis and the selected fill gases are combined to provide white light with minimal color separation from the discharge lamp.

Abstract: The invention relates to a high-pressure sodium lamp provided with an elongate discharge vessel in which the pressure P in the operative condition of the lamp is at least 170.times.10.sup.3 Pa. The lamp is suitable to be operated with a power of periodically alternating value, which power comprises at least one component having a frequency .nu..sub.i which satisfies i-0.45.ltoreq.2.35.nu..sub.i Le/e.ltoreq.i+0.45 where i is an integral positive number, c is the speed of sound in the gaseous part of the filling and L.sub.e is the effective length of the discharge vessel. According to the invention, the relation is satisfied: M.nu..sub.i .multidot.f.sub.i .multidot.P.multidot.d .ltoreq.185, in which M.nu..sub.i is the modulation depth of the power component having a frequency .nu..sub.i, f.sub.i is a geometric lamp factor and d the average inner diameter of the discharge vessel. In this manner, the operation of the lamp is free of arc instabilities due to longitudinal acoustic resonances.

Abstract: A metal halide arc discharge lamp having a gaseous fill within the outer envelope and means for suppressing convection currents within such fill; and methods of operating and constructing such lamps. A light-transmissive sleeve or enclosure surrounding the arc tube laterally and about at least one end thereof is so shaped and mounted with respect to the arc tube as to insure that the Rayleigh Number, a quantitative measure of convection flow, in the atmosphere laterally surrounding the arc tube will be less than 5.times.10.sup.4 during operation of the lamp whereby excessive convective heat loss in such lamp will be effectively suppressed.

Abstract: An ultraviolet light source includes a volume filled with a dose of AlCl.sub.3 and an inert gas. No mercury is used. During electrical discharge excited states of AlCl.sub.3, AlCl.sub.2, and AlCl emit light, with AlCl having a broad ultraviolet emission peaking at about 261.4 nm. The source may be energized with or without internal electrode. Phosphors may be employed to convert the ultraviolet to visible light. The lamp's envelope may be aluminosilicate coated quartz.

Abstract: A compact fluorescent lamp has an outer envelope in which there is supported a capsule containing a mercury-free fill comprised of aluminum trichloride. The fill is energized to produce a plasma discharge which emits ultraviolet and visible radiation. Phosphor, in the form of a particulate layer or a gas, converts the ultraviolet into visible light. The lamp may contain electrodes or be electrodeless. In the electrodeless embodiment RF energy may be capacitively or inductively coupled to the fill.