Abstract: A lamp is provided having an arctube having a light-transmitting envelope. The arctube is surrounded by a gaseous medium confined by a containment envelope such as a hermetic shroud. The gaseous medium is preferably He or H2 or Ne or another gas whose thermal conductivity is greater than that of N2 at 800° C., or a mixture thereof, to help cool the arctube. The inside and/or outside of the shroud may be coated with a diffusion barrier. To help cool the hot spot of the arctube the gap between the shroud and the envelope can be made small, the portion of the shroud wall near the arc can be thickened, the arctube can be offset above the longitudinal axis of the shroud, and the return lead of the arctube can be located between the shroud and the arctube.

Abstract: A lamp is provided having an arctube having a light-transmitting envelope. The arctube is surrounded by a gaseous medium confined by a containment envelope such as a hermetic shroud. The gaseous medium is preferably He or H2 or Ne or another gas whose thermal conductivity is greater than that of N2 at 800° C., or a mixture thereof, to help cool the arctube. The inside and/or outside of the shroud may be coated with a diffusion barrier. To help cool the hot spot of the arctube the gap between the shroud and the envelope can be made small, the portion of the shroud wall near the arc can be thickened, the arctube can be offset above the longitudinal axis of the shroud, and the return lead of the arctube can be located between the shroud and the arctube.

Abstract: A lamp is provided having an arctube having a light-transmitting envelope. The arctube is surrounded by a gaseous medium confined by a containment envelope such as a hermetic shroud. The gaseous medium is preferably He or H2 or Ne or another gas whose thermal conductivity is greater than that of N2 at 800° C., or a mixture thereof, to help cool the arctube. The inside and/or outside of the shroud may be coated with a diffusion barrier. To help cool the hot spot of the arctube the gap between the shroud and the envelope can be made small, the portion of the shroud wall near the arc can be thickened, the arctube can be offset above the longitudinal axis of the shroud, and the return lead of the arctube can be located between the shroud and the arctube.

Abstract: A high brightness discharge light source having improved thermal balance characteristics includes a lamp envelope having an arc chamber formed therein and a pair of electrodes extending into opposite ends of the arc chamber so as to be displaced from one another by a distance of no greater than 4 mm. A fill disposed within the arc chamber is excited to a discharge state upon the introduction of an excitation energy coupled through the pair of electrodes. The light source is operated vertically so that one of the electrodes is disposed at the top region and the other electrode is disposed at the bottom region of the arc chamber. The arc chamber is formed having a diameter dimension which is just larger than the spacing between the electrodes, and a height dimension which is approximately twice the diameter dimension. The diameter dimension is substantially uniform along the length of the arc chamber.

Abstract: A linear double ended lamp can be modified into a number of non-linear arrangements by heating selected regions of the lamp ends to the softening temperature and bending the lamp ends to a desired angular configuration. Preferably, the lamp ends are bent across the sealing foil that is hermetically sealed to the lamp envelope. One or both ends of the lamp can be bent as desired to define a variety of configurations. According to the method of forming the bent double ended lamp, selected regions of the lamp are raised above the softening temperature while the remainder of the lamp is maintained at a lower temperature. Preferably, the lamp ends are bent along an axis offset and parallel to the longitudinal axis of the lamp to prevent accumulation of material.

Abstract: The invention relates to an electrode-inlead assembly for electrical lamps which comprises a lead-in-wire connected to a foil made of refractory metal and the foil is connected to a shank made of refractory metal and supporting the electrode.The object of the invention is, that the shank is made of two parallel rods which are joined by their one end portions, and their opposite end portions are welded to the foil, so that the foil is sandwiched between the rods.

Abstract: A high pressure discharge lamp with a thermally improved anode, as well as a method of making such a lamp, are disclosed. The lamp includes a refractory arc tube with a hermetically sealed arc chamber, a fill in the arc chamber for facilitating light generation, and an anode and a cathode extending into the hermetically sealed arc chamber and being spaced apart from each other. The anode comprises a shank of refractory metal, a cylindrically shaped refractory metal sleeve on a portion of the shank, and an end proximally facing the cathode. The anode end comprises a substantially solid mass of refractory metal, and is integrally joined to both the shank and the metal sleeve to facilitate heat flow from the anode end to the shank and sleeve. The anode end preferably is generally shaped as a hemisphere facing the cathode. The refractory metal sleeve is preferably one or more layers of a helically wound refractory metal wire having an outer diameter more than twice a diameter of the shank.

Abstract: A high brightness discharge light source includes an arctube having an arc chamber formed therein and in which is disposed a fill of gas energizable to a discharge condition. At least two electrodes extend into the arc chamber and are separated by an arc gap of between 2 and 3.5 mm. The dose of mercury disposed in the arc chamber and various arc tube dimensions are selected so as to achieve a balance between three constraints including operating voltage thereby defining lamp efficacy, convective stability and structural integrity of the discharge lamp. A balance between arc gap, arc chamber diameter, wall thickness and the mercury density of the lamp yield a discharge lamp which achieves a light output on the order of 50,000 lumens per square centimeter.

Abstract: A xenon metal halide lamp having an improved electrode structure that is particularly suited for automotive applications is disclosed. The electrode is comprises of a tip portion that is located at one end of a shank with the shank having a filament coiled therearound. The tip and shank portions are designed to allow for high initial current during starting and low current during operation. The coil filament is situated in opposite neck portions of an envelope forming the light source so as to; (1) cause the electrodes to be axially aligned within the light source; (2) keep the shank of the electrode from intimate contact with the envelope thereby preventing the condensation of the mercury and allowing for substantial vaporization of the metal halide ingredients at the neck portion; and (3) prevent the thermal expansion of the electrode from cracking the envelope.