US4093889A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low-pressure mercury vapor discharge lamp
Assignee: US Philips Corp
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Filing: 1977-02-03
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Granted: 1978-06-06
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Expires: 1997-02-03
Abstract
Abstract A low-pressure mercury vapor discharge lamp, having a discharge space containing thermally emitting electrodes and a mercury amalgam which is composed of mercury, bismuth, tin and lead. This amalgam causes the mercury vapor pressure to remain stable at the value of 6 × 10 -3 torr which is the optimum value for the conversion of electric energy into ultraviolet radiation over a wide temperature range. In addition, the mercury vapor pressure at room temperature is still sufficiently high to ensure rapid starting.
Inventors
- 👤 Jan Bloem
- 👤 Albert Bouwknegt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:29
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/70; H01J61/72
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
31 words
A low-pressure mercury vapour discharge lamp which comprises a discharge space and disposed in said space two thermally emitting electrodes and a mercury amalgam composed of mercury, bismuth, tin and lead.
Claim 2
Dependent Claim
31 words
A low-pressure mercury vapour discharge lamp which comprises a discharge space and disposed in said space two thermally emitting electrodes and a mercury amalgam composed of mercury, bismuth, tin and lead.
Claim 3
Dependent Claim
39 words
A low-pressure mercury vapour discharge lamp as claimed in claim 1 wherein the ratio of the sum of the number of atoms of bismuth, tin and lead to the number of atoms of mercury is between 0.85:0.15 and 0.98:0.02.
Claim 4
Dependent Claim
39 words
A low-pressure mercury vapour discharge lamp as claimed in claim 1 wherein the ratio of the sum of the number of atoms of bismuth, tin and lead to the number of atoms of mercury, is between 0.85:0.15 and 0.94:0.06.
Claim 5
Dependent Claim
41 words
A low-pressure mercury vapour discharge lamp as claimed in claim 1 wherein the ratio of the number of atoms of bismuth to the number of atoms of tin to the number of atoms of lead is approximately the eutectic ratio 48:24:28.
References Cited (Backward Citations)
US3521110A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-06-05 | 1981-12-05 | 1982-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-05 | 1985-12-05 | 1986-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-05 | 1989-12-05 | 1990-06-06 | $7700.00 | Window Closed / Lapsed |