US3599028A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mercury vapor discharge lamp employing europium activated calcium and/or strontium pyrophosphate luminescent material
Assignee: US Philips Corp
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Filing: 1968-02-28
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Granted: 1971-08-10
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Expires: 1988-02-28
Abstract
Abstract Mercury-vapor discharge lamp employing as a luminescent material a bivalent europium activated pyrophosphate of calcium or strontium and combinations thereof.
Inventors
- 👤 Willem Lambertus Wanmaker
- 👤 Johannes Wilhelmus Ter Vrugt
- 👤 Johannus Godefridu Verlijsdonk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:35
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7728; C09K11/7737; C09K11/7738
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
14 words
A mercury vapor discharge lamp as claimed in claim 1 wherein: 0.01 p 0.04.
Claim 2
Dependent Claim
33 words
A mercury vapor discharge lamp as claimed in claim 2, characterized in that a light reflecting layer of titanium dioxide is provided between the support of the luminescent material and said luminescent material.
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) | 1974-08-09 | 1975-02-08 | 1975-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-09 | 1979-02-08 | 1979-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-09 | 1983-02-08 | 1983-08-10 | $7700.00 | Window Closed / Lapsed |