US3781586A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Long lifetime mercury-metal halide discharge lamps
Assignee: General Electric Co
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Filing: 1972-12-04
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Granted: 1973-12-25
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Expires: 1992-12-04
Abstract
Abstract An improved mercury-metallic halide vapor arc discharge lamp in which sodium is present as a principal radiating specie and is added as the iodide to a mercury charge within a discharge envelope either solely or in the presence of other metallic iodides to produce a pleasing near-white emission, contains within the discharge envelope a sufficient quantity of elemental tin to prevent the existence of free iodine therein, thus achieving a greatly extended lifetime.
Inventors
- 👤 P Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:54
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/12; H01J61/18; H01J61/22
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
33 words
The lamp of claim 1 wherein said mercury is present in a sufficient quantity as to provide within said envelope under operating conditions a vapor pressure thereof of from 1 to 20 atmospheres.
Claim 2
Dependent Claim
25 words
The lamp of claim 2 wherein said inert starting gas is present within said envelope at a partial pressure of approximately 5 to 50 torr.
Claim 3
Dependent Claim
47 words
The lamp of claim 2 wherein said sodium iodide is present in a sufficient quantity so as to provide under lamp operating conditions a partial pressure therein within said discharge envelope of approximately 0.05 to 25 torr and retain a substantial quantity thereof in the unvaporized statE.
Claim 4
Dependent Claim
27 words
The lamp of claim 4 wherein said sodium iodide is present in a quantity of approximately 2 to 6 mgs per cubic centimeter of discharge envelope volume.
Claim 5
Dependent Claim
35 words
The lamp of claim 5 wherein said elemental tin is present in a quantity sufficient to combine with all free iodine evolved within said lamp during the lifetime thereof by the cleanup of sodium therefrom.
Claim 6
Dependent Claim
32 words
The lamp of claim 5 wherein said elemental tin is present in a quantity ranging from approximately 0.1 to 0.5 mole thereof for each of the mole of sodium iodide present therein.
Claim 7
Dependent Claim
52 words
The lamp of claim 4 wherein said sodium iodide is present in a quantity of approximately 2 to 6 mgs per cubic centimeter of the volume of said discharge envelope and said elemental tin is present in a quantity of approximately 0.1 to 0.5 mole for each mole of sodium iodide present.
Claim 8
Dependent Claim
34 words
The lamp of claim 4 wherein said charge contains at least one additional vaporizable dissociable halide of a light emitting metal which combines with the emission of sodium to provide a desired spectral rendition.
Claim 9
Dependent Claim
32 words
The lamp of claim 4 wherein said discharge envelope also contains quantities of thallium iodide and indium iodide sufficient to cause the spectral emission from said lamp to be essentially white light.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-24 | 1977-06-25 | 1977-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-24 | 1981-06-25 | 1981-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-24 | 1985-06-25 | 1985-12-25 | $7700.00 | Window Closed / Lapsed |