High pressure electric discharge device with hafnium getter
AssigneeGTE Sylvania Incorporated
InventorsWilliam M. Keeffe, Frederic Koury
Life of this patent
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Abstract
A thin foil of hafnium or a hafnium alloy is disposed within a high pressure metal halide discharge lamp for selectively gettering any hydrogen contaminant within the lamp. In one embodiment a long strip of hafnium foil is welded along the current return wire which extends from the remote end of the arc tube to the base of the lamp, while in another embodiment, bowed-out strips are welded to support straps on each of the arc tube press seals. In this manner, a significant portion of the hafnium getter is disposed in a location where it is subjected to operating temperatures lower than about 330.degree.C.
Claims20
A lamp comprising:
- an hermetically sealed envelope;
- an inert gas in said envelope;
- electrically energizable means for providing a source of light within said envelope;
- and means for selectively gettering hydrogen within said envelope, said gettering means comprising hafnium or an alloy thereof.
A high pressure electric discharge device comprising:
- a bulbous glass envelope;
- an arc tube disposed within said bulbous envelope;
- means to form an electric discharge within said arc tube;
- and getter means disposed within said bulbous envelope for selectively gettering hydrogen, said getter means comprising hafnium or an alloy thereof.
Dependencies are inferred from the claim text.