Abstract: Discharge tubes for a lamp include a body portion with a first end, a second end, and a tubular member defining an interior area. The tubular member extends along an elongated axis between the first end and the second end. The discharge tube further includes a first end portion provided at the first end of the body portion. The first end portion includes a first tubular extension having a first through passage in communication with the interior area. The first end portion further includes a first transition section connected between the first tubular extension and the body portion.

Abstract: Discharge tubes for a lamp include a body portion with a first end, a second end, and a tubular member defining an interior area. The tubular member extends along an elongated axis between the first end and the second end. The discharge tube further includes a first end portion provided at the first end of the body portion. The first end portion includes a first tubular extension having a first through passage in communication with the interior area. The first end portion further includes a first transition section connected between the first tubular extension and the body portion.

Abstract: Tips for electrodes that are adapted to be applied to a ceramic halide lamp are formed by backwinding tungsten wire into a coil onto a tungsten shank. The outer diameter of the coil of tungsten wire is maintained sufficiently small so that the electrode tips can be inserted through openings in the legs of the electric arc tube of the ceramic halide lamp and the tungsten coil positioned within the hollow interior of the electric arc tube.

Abstract: Discharge tubes for a lamp include a body portion with a first end, a second end, and a tubular member defining an interior area. The tubular member extends along an elongated axis between the first end and the second end. The discharge tube includes a first end portion provided at the first end of the body portion. The first end portion includes a first tapered portion that is tapered in a direction extending substantially perpendicular from the elongated axis. The first tapered portion includes an interior surface facing the interior area. The tapered portion spans between a maximum extent in the direction of the elongated axis and a minimum extent in the direction of the elongated axis.

Abstract: Discharge tubes for a lamp include a body portion with a first end, a second end, and a tubular member defining an interior area. The tubular member extends along an elongated axis between the first end and the second end. The discharge tube further includes a first end portion provided at the first end of the body portion. The first end portion includes a first tubular extension having a first through passage in communication with the interior area. The first end portion further includes a first transition section connected between the first tubular extension and the body portion.

Abstract: Discharge tubes for a lamp include a body portion with a first end, a second end, and a tubular member defining an interior area. The tubular member extends along an elongated axis between the first end and the second end. The discharge tube includes a first end portion provided at the first end of the body portion. The first end portion includes a first tapered portion that is tapered in a direction extending substantially perpendicular from the elongated axis. The first tapered portion includes an interior surface facing the interior area. The tapered portion spans between a maximum extent in the direction of the elongated axis and a minimum extent in the direction of the elongated axis.

Abstract: A ceramic body (14) for a discharge vessel (12) includes a central barrel portion (60) and two end plus (64, 66), which close opposite ends of the barrel. Main electrode (32, 34) and an initiator electrode 50 are supplied with power via conductors in leg members (70, 76, 72). In one embodiment, a first electrode 32 and the initiator electrode are supplied with current through two separate leg members. In another embodiment, a dual electrode leg member is provided with two bores (124, 126).

Abstract: A ceramic body (14) for a discharge vessel (12) includes a central barrel portion (60) and two end plus (64, 66), which close opposite ends of the barrel. Main electrode (32, 34) and an initiator electrode 50 are supplied with power via conductors in leg members (70, 76, 72). In one embodiment, a first electrode 32 and the initiator electrode are supplied with current through two separate leg members. In another embodiment, a dual electrode leg member is provided with two bores (124, 126).

Abstract: The present invention concerns a process of treating an energizing electrode for use in a metal halide lamp. Lamp energizing electrodes are placed into a support container and the support container is then placed within an oven that bakes the electrodes at an elevated temperature. Hydrogen is caused to flow through the support container at a rate of from 5 to 60 liters per minute while the temperature is maintained within the oven between 2000 and 3200 degrees C. In accordance with an exemplary embodiment of the invention, the temperature is maintained within the oven at 2400 and 2600 degrees C., the dew point of the hydrogen is less than minus 40 degrees C. and the electrodes are baked for a period of 10 to 240 minutes. This process treats the electrodes in the support container and results in lamps having superior maintenance of lamp output as measured in lumens of output.

Abstract: To achieve the foregoing objects and in accordance with the purpose of the invention, as embodied and broadly described herein, the metal halide lamp of this invention comprises a vitreous arc tube containing an ionizable medium and having electrodes sealed into opposed ends of the arc tube. An outer envelope encloses the arc tube and includes one end accommodating inleads sealed therethrough. A base is attached to the outer envelope having input terminals, the input terminals being connected to the inleads which in turn are connected to the tungsten electrodes. A mount is provided to support the arc tube within the outer envelope. The ionizable medium will include mercury, a metal halide, and an inert gas selected from the group consisting of argon, krypton, and xenon and mixtures thereof. In addition, a starting circuit having an open circuit voltage of at least 200 volts RMS will be provided. The inert gas having a pressure of at least about 70 torr.

Abstract: A metal halide lamp, having a cold fill pressure of at least 50 torr, incorporates a starter circuit with an active device to protect the diode included therein. The active portion of the starter circuit, either removes a voltage multiplying circuit portion, from the starter circuit or shorts out the diode by shunting action of the switch. The voltage multiplier circuit portion is connected across the main electrodes, wherein the voltage multiplier circuit portion increases the starting voltage applied to the starter electrode.

Abstract: A high-pressure discharge lamp is disclosed having a discharge vessel, an outer bulb enclosing said discharge vessel and defining an intervening space therebetween, a UV-enhancer positioned in the space between the outer bulb and the discharge vessel, the UV-enhancer provided with a wall fabricated of a ceramic material and an internal electrode, wherein an end portion of the UV-enhancer is closed with a compressive seal.

Abstract: The invention relates to a high-pressure discharge lamp provided with a discharge vessel with a ceramic wall which has an outer surface on which a metallic coating is present. According to the invention, the coating is a metal layer sintered on the ceramic wall, which sintering process takes place during sintering of the discharge vessel so as to achieve translucence.

Abstract: The luminous efficacy and color rendering index of a metal halide lamp containing sodium iodide and scandium iodide is increased, and the color correlated temperature is decreased, by the addition of critical amounts of thallium iodide and lithium iodide.

Abstract: A metal halide high intensity discharge lamp having an arc tube assembly including a pair of discharge electrodes and a pair of starting electrodes. Each starting electrode is adjacent a respective discharge electrode. During starting, the lamp makes the glow discharge to arc discharge transition in a substantially shorter time than a lamp with a single starting electrode, and exhibits a substantially improved lumen maintenance.

Abstract: A high-pressure discharge lamp having an internal metal shield for containing fragments in the event the lamp discharge vessel ruptures. The metal shield is mounted in an electrically isolated condition to avoid acceleration of sodium loss from the discharge vessel due to the proximity of the discharge vessel and the metal shield.

Abstract: The luminous efficacy of a metal halide lamp containing sodium iodide and scandium iodide is increased, while color rendering index is maintained or improved by the addition of critical amounts of thallium iodide.

Abstract: An HID lamp having parts of its internal metal support covered with a layer of material having a photoelectric work function greater than 5.0 electron volts to reduce internal photoelectron production. The material may be granular zirconium oxide having a photoelectric work function of 5.8 eV.