Abstract: A reflector lamp 10 has a vitreous outer envelope 12 formed of a concave reflector 14 and a light-transmitting 16 cover peripherally sealed thereto. The concave reflector and cover are symmetrically arrayed about a longitudinal axis 18 and a substantially cylindrical, hollow neck 20 having a given depth is affixed to the concave reflector opposite the cover. The neck 20 also is symmetrically arrayed about the longitudinal axis 18 and has a substantially closed bottom 21. At least two eyelets, 22, 24, respectively, are sealed in the bottom 21 and a light source capsule 26 is positioned in the concave reflector and aligned with the longitudinal axis 18. The light source capsule 26 has a first end 28 situated in the neck 20 and a second end 30 extending into the concave reflector. The light source capsule 26 comprises a quartz arc tube 32 containing an arc generating and sustaining medium and a surrounding aluminosilicate glass shroud 34.

Abstract: A highly efficient discharge lamp has a color rendering index of about 85, a lumens per watt rating of about than 90, a correlated color temperature of 3000.degree. K., and a wall loading of about 21 W/cm.sup.2. The lamp has an outer glass envelope and a pair of electrical conductors extending into the interior of the glass envelope; a quartz discharge tube disposed within the outer envelope and including a pair of spaced electrodes which are electrically connected to the electrical conductors for creating an electrical discharge during operation of the lamp, the discharge tube having an arc chamber. An arc generating and sustaining medium is provided within the arc chamber and includes the halides of sodium, scandium, lithium, dysprosium and thallium, a fill gas selected from argon and xenon, and a given quantity of mercury to achieve a desired lamp voltage. In a preferred embodiment of the invention the halides are iodides and are present in the mole ratio of about 24-44:1:9.

Abstract: A scandium halide and alkali metal halide discharge lamp has a chemical fill in the arc tube comprising an inert starting gas, mercury, alkali metal iodides, scandium iodide and platinum metal as an additive for reducing the tendency of the lamps to discolor during operation.

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: 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: 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 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 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 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.

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: 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 about a distance to provide a substantially uniform current for lamps in the range of about 35 to 150 watts.