Oxidized electrodes as oxygen dispensers in metal halide lamps
AssigneeGeneral Electric Company
InventorsAgoston BOROCZKI, Peter HORVATH, Laszlo UGROSDY, Sandor SEBOK, Akos PETER
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Abstract
An electrode for dosing oxygen into a metal halide lamp, where the electrode supplies oxygen during lamp operation in an amount effective to maintain a wall cleaning tungsten halogen chemical cycle. Use of the oxygen dosing electrode increases the lumen maintenance of the lamp to 80% or higher at 6000 hours. A method for making an oxidized electrode for use as an oxygen dispenser into the discharge vessel of a metal halide lamp is also provided.
Claims20
An electrode for dosing oxygen into a metal halide lamp, wherein the electrode comprises a tungsten tip, a molybdenum region, and a niobium leadwire, and wherein either the tungsten tip or the molybdenum region, or both, is oxidized;
- and
- wherein the oxidized portion supplies oxygen during lamp operation in an amount effective to maintain a wall cleaning tungsten halogen chemical cycle.
An electrode for dosing oxygen into a metal halide lamp, comprising an oxidized molybdenum overcoil.
A method of making an oxidized electrode for use as an oxygen dispenser into the discharge vessel of a metal halide lamp comprising the steps;
- placing the electrode to be oxidized in an electrochemical cell containing an electrolyte so that the tungsten tip and molybdenum region are exposed to the electrolyte and passing a current through the electrochemical cell so that WO3 is formed on the tungsten tip and/or MoO3 is formed on the molybdenum region.
Dependencies are inferred from the claim text.