Abstract: A metal halide high intensity discharge lamp including a carbon monoxide additive in the arc tube fill to improve lumen maintenance is provided. The metal halide discharge lamp of the present invention comprises: an outer sealed glass envelope; a pair of electrical conductors sealed into and passing through the glass envelope; an arc tube disposed within the outer glass envelope, the arc tube including a pair of spaced electrodes therein with the electrodes being electrically connected to the electrical conductors such that one electrode is electrically connected to one electrical conductor; a chemical fill disposed within the arc tube, the chemical fill comprising mercury, metal halide additives, carbon monoxide, and a starting gas; and a support structure disposed within the outer glass envelope to support the arc tube therein.

Abstract: The present disclosure describes a method for determining the condensate location within an HID lamp. The method involves monitoring current and voltage waveforms during the glow phase of lamp starting. If the voltage drop during the glow phase is low with a corresponding high current, then the volatile component of the lamp fill has condensed on the electrodes during the previous cool down period. If the voltage drop is high and current is low then most of the condensate has localized on the arc tube wall. An automated detection apparatus is used to carry out the measurements to determine condensate location.

Abstract: A low wattage metal halide lamp having improved CRI is disclosed. The low wattage metal halide discharge lamp of the present invention comprises an outer sealed glass envelope; a pair of electrical conductors sealed into and passing through the glass envelope; an arc tube disposed within the outer glass envelope, the arc tube including a pair of spaced electrodes therein with the electrodes being electrically connected to the electrical conductors such that one electrode is electrically connected to one electrical conductor; a chemical fill disposed within the arc tube, the chemical fill comprising mercury, scandium metal, sodium iodide, scandium iodide, lithium iodide, and a starting gas; and a support structure disposed within the outer glass envelope to support the arc tube therein, the support structure being electrically isolated from the electrical circuit of the lamp.

Abstract: A metal halide high intensity discharge lamp including a carbon monoxide additive in the arc tube fill to improve lumen maintenance is provided. The metal halide discharge lamp of the present invention comprises: an outer sealed glass envelope; a pair of electrical conductors sealed into and passing through the glass envelope; an arc tube disposed within the outer glass envelope, the arc tube including a pair of spaced electrodes therein with the electrodes being electrically connected to the electrical conductors such that one electrode is electrically connected to one electrical conductor; a chemical fill disposed within the arc tube, the chemical fill comprising mercury, metal halide additives, carbon monoxide, and a starting gas; and a support structure disposed within the outer glass envelope to support the arc tube therein.

Abstract: An improved metal halide discharge lamp is provided. The improved metal halide includes an arc tube having a pair of electrodes and containing a fill including an inert starting gas, mercury, and metal halides; and an outer envelope enclosing the arc tube. The entire outer surface of the arc tube is coated with a heat reflective material to improve lamp efficiency.

Abstract: An arc tube for horizontal operation and arc discharge lamp employing same wherein the arc tube has devices in each end for suppressing crystalline deposit penetration into the arc tube press seals along the shanks of the main electrodes. Experimental evidence shows that crystalline penetration into a press seal weakens the press seal and is the likely cause of an occasional arc tube burst during lamp operation, a problem well known in the art. In a preferred embodiment, a starting electrode is mounted above the main electrode in each end of the operationally positioned arc tube. So placed, each starting electrode is upstream in the convective flow of the gaseous fill within the arc tube. Each starting electrode may be electrically coupled with the lamp's circuit or electrically isolated therefrom without substantially affecting the starting electrode's ability to suppress crystalline penetration of the press seal about the base of the adjacent main electrode.

Abstract: A low wattage metal halide discharge lamp includes a arc tube having a temperature equalizing means telescoped thereover and an evacuated outer envelope enclosing the arc tube and convection current reducing means.

Abstract: A double-enveloped lamp having a shield surrounding a light-source capsule within a thick-walled outer envelope so that the lamp may be safely operated without necessity of a protective fixture. In the rare event of a burst of the light-source capsule, the shield absorbs and dissipates a portion of the burst energy sufficient to permit the thick-walled outer envelope to remain intact and contain shards and other internal parts within the lamp. In alternate embodiments, the shield may be reinforced, such as with a wire mesh, or the outer envelope may be reinforced, such as with a polymer coating, or both. A thin-walled capsule may be employed in combination with a shield and thick outer envelope. A lamp in accordance with the invention provides the unexpected benefits of improved luminous efficacy and better color rendering characteristics, since the presence of an optimally positioned shield causes the operation of the light-source capsule to be more nearly isothermal.

Abstract: An improved metal-halide arc discharge lamp includes an arc tube having a substantially cylindrical body surrounded laterally by a substantially cylindrical heat-conserving sleeve within an evacuated outer envelope. The ratio of the outer radius of the arc tube divided by the inner radius of the sleeve falls within an optimum range of approximately 0.54 to approximately 0.68, and preferably within a range of approximately 0.60 to approximately 0.63. A lamp constructed in accordance with the invention exhibits improved luminous efficacy and color rendering in comparison to prior art counterparts. The improved performance is believed to be attributable to the more nearly isothermal operation of the arc tube for a given wall loading.

Abstract: The present invention is directed to a method for the elimination of end pockets in metal halide arc tube envelopes (or other irregularities) in order to improve the color stability thereof.The present invention is also directed to the improved lamps having reduced or substantially eliminated end pockets.The magnitude of this improvement will increase with decreasing arc tube size, since in smaller arc tubes, the tube ends represent a larger fraction of the overall inner surface of the device.

Abstract: The present invention is directed to a method for the elimination of end pockets in metal halide arc tube envelopes (or other irregularities) in order to improve the color stability thereof.The present invention is also directed to the improved lamps having reduced or substantially eliminated end pockets.The magnitude of this improvement will increase with decreasing arc tube size, since in smaller arc tubes, the tube ends represent a larger fraction of the overall inner surface of the device.

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 discharge lamp comprises an arc tube containing a chemical fill including mercury and metal halides and having first and second electrodes respectively sealed at opposite ends thereof. An outer envelope surrounds the arc tube and has first and second terminals for electrical connection thereto. A source of ultraviolet radiation is provided within the outer envelope proximate the arc tube for producing radiation which illuminates the path between the electrodes of the arc tube to decrease the amount of time for generating a gaseous discharge therebetween. The ultraviolet light source includes an envelope of ultraviolet light transmitting material containing a fill material and having a single electrode sealed in one end thereof. The single electrode is electrically coupled to one electrode of the arc tube.

Abstract: A metal halide arc discharge lamp comprises an arc tube containing a chemical fill including mercury and metal halides and having first and second electrodes respectively sealed at opposite ends thereof. An outer envelope surrounds the arc tube and has first and second terminals for electrical connection thereto. An electrodeless source of ultraviolet radiation is provided within the outer envelope proximate the arc tube for producing radiation which illuminates the path between the electrodes of the arc tube to decrease the amount of time for generating a gaseous discharge therebetween. The ultraviolet light source includes an envelope of ultraviolet light transmitting material having opposing ends. Portions of the envelope of the ultraviolet light source are capacitively coupled across the electrodes of the arc tube such that the source produces ultraviolet radiation during lamp starting when the first and second terminals of the lamp are energized.

Abstract: An improved metal-halide arc discharge lamp includes an arc tube having a substantially cylindrical body surrounded laterally by a substantially cylindrical heat-conserving sleeve within an evacuated outer envelope. The ratio of the outer radius of the arc tube divided by the inner radius of the sleeve falls within an optimum range of approximately 0.54 to approximately 0.68, and preferably within a range of approximately 0.60 to approximately 0.63. A lamp constructed in accordance with the invention exhibits improved luminous efficacy and color rendering in comparison to prior art counterparts. The improved performance is believed to be attributable to the more nearly isothermal operation of the arc tube for a given wall loading.

Abstract: A light-source containment device and lamp employing such device; a metal halide arc discharge lamp having a light-transmissive shield enclosing the arc tube and a wire mesh surrounding the shield. In the event the arc tube bursts causing shattering of the shield, the wire mesh substantially restricts shards of the shield and arc tube from shattering the outer envelope of the lamp thereby providing improved safety characteristics of the lamp. A similar containment device encloses the light-source capsule and protects against lamp-containment failures in tungsten halogen lamps.

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: A fill composition for a high intensity discharge device including mercury, niobium oxytrihalide, and a molecular stabilization agent is provided. The molar ratio of niobium oxytrihalide to the molecular stabilization agent in the fill is in the range of from about 5:1 to about 7.5:1. Niobium oxytrihalide is present in the fill in sufficient amount to produce, by dissociation in the discharge, atomic niobium, niobium oxide, NbO, and niobium dioxide, NbO.sub.2, with the molar ratio of niobium-containing vapor species to mercury in the fill being in the range of from about 0.01:1 to about 0.50:1; and mercury pressure of about 1 to about 50 atmospheres at lamp operating temperature. There is also provided a high intensity discharge device comprising a sealed light-transmissive arc tube; the arc tube including the above-described fill; and an energizing means for producing an electric discharge within the arc tube.

Abstract: A low wattage single-ended metal halide arc discharge lamp has an isothermal arc chamber with an outer diameter (t) substantially equal to the product of a first constant and the lamp wattage plus a second constant; a fill gas and a pair of electrical conductors sealed into and passing through one end of the arc chamber to provide a pair of electrodes therein having a spacing therebetween of a distance to provide a substantially uniform current for lamps in the range of about 35 to 150 watts.

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.