Patent US4302699A successfully refreshed from Google Patents.
US4302699A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low wattage metal halide arc discharge lamp having optimum efficacy
Assignee: Osram Sylvania Inc
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Filing: 1980-03-24
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Granted: 1981-11-24
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Expires: 2000-03-24
Abstract
Abstract A single ended metal halide arc discharge lamp contains mercury, sodium halide, scandium, scandium halide and a starting gas. The molar ratio of sodium halide to scandium halide is between about 5 to 8 in order to obtain optimum luminous efficacy.
Inventors
- 👤 William M. Keeffe
- 👤 Harold L. Rothwell, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:53
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/12; H01J61/18
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
74 words
A single-ended low wattage metal halide arc discharge lamp comprising: an arc tube having a press seal at one end thereof, two main electrodes embedded in the press seal and extending into the arc tube, the arc tube containing mercury, sodium halide, scandium, scandium halide and a starting gas, the molar ratio of sodium halide to scandium halide during normal operation being between about 5 to 8 in order to obtain optimum luminous efficacy.
Claim 2
Dependent Claim
74 words
A single-ended low wattage metal halide arc discharge lamp comprising: an arc tube having a press seal at one end thereof, two main electrodes embedded in the press seal and extending into the arc tube, the arc tube containing mercury, sodium halide, scandium, scandium halide and a starting gas, the molar ratio of sodium halide to scandium halide during normal operation being between about 5 to 8 in order to obtain optimum luminous efficacy.
Claim 3
Dependent Claim
20 words
The lamp of claim 1 wherein the fill initially added to the arc tube included mercuric iodide and scandium metal.
Claim 4
Dependent Claim
34 words
The lamp of claim 2 wherein the amount of said scandium metal was in excess of that amount needed to react with all the iodine in said mercuric iodide to form ScI 3 .
Claim 5
Dependent Claim
114 words
A single-ended low wattage metal halide arc discharge lamp comprising: an arc tube having a press seal at one end thereof, two main electrodes embedded in the press seal and extending into the arc tube, the arc tube containing an initial filling that includes mercury, sodium halide, scandium, a starting gas and a metal halide that reacts with scandium to form scandium halide, the reaction of said metal halide with scandium being substantially complete after about 100 hours of lamp operation, the molar ratio of sodium halide to scandium halide being between about 5 to 8 after said substantially complete reaction, there remaining elemental scandium in the arc tube after said substantially complete reaction.
Claim 6
Dependent Claim
114 words
A single-ended low wattage metal halide arc discharge lamp comprising: an arc tube having a press seal at one end thereof, two main electrodes embedded in the press seal and extending into the arc tube, the arc tube containing an initial filling that includes mercury, sodium halide, scandium, a starting gas and a metal halide that reacts with scandium to form scandium halide, the reaction of said metal halide with scandium being substantially complete after about 100 hours of lamp operation, the molar ratio of sodium halide to scandium halide being between about 5 to 8 after said substantially complete reaction, there remaining elemental scandium in the arc tube after said substantially complete reaction.
Claim 7
Dependent Claim
12 words
The lamp of claim 4 wherein said metal halide is mercuric iodide.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-11-23 | 1985-05-25 | 1985-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-23 | 1989-05-25 | 1989-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-23 | 1993-05-25 | 1993-11-24 | $7700.00 | Window Closed / Lapsed |