US4607191A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Protection film for improved phosphor maintenance and increased time-integrated light output
Assignee: Osram Sylvania Inc
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Filing: 1984-11-13
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Granted: 1986-08-19
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Expires: 2004-11-13
Abstract
Abstract In a fluorescent lamp having a phosphor coating, a maintenance improving and light output increasing film comprising yttrium oxide and at least one U.V. absorber is applied over the phosphor. The U.V. absorber is effective in the absorption of a greater amount of 185 nm radiation than 254 nm radiation from the plasma discharge. The film is most beneficial when applied over alkaline earth halophosphate phosphors at a film thickness of from about 50 angstroms to about 500 angstroms.
Inventors
- 👤 John M. Flaherty
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:48
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/38; H01J61/42; H01J61/48
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
103 words
A fluorescent lamp having improved maintenance and integrated light output comprising: a tubular, hermetically sealed, glass envelope; electrodes sealed in the ends of said envelope; an arc generating and sustaining medium including mercury within said envelope for producing a plasma discharge when a predetermined voltage is applied across said electrodes; a phosphor coating adhering to the interior surface of said envelope; and a non-particulate film overlying said phosphor wherein said film comprises yttrium oxide and at least one U.V. absorber, said absorber being effective in the absorption of a greater amount of 185 nm radiation than 254 nm radiation from said plasma discharge.
Claim 2
Dependent Claim
103 words
A fluorescent lamp having improved maintenance and integrated light output comprising: a tubular, hermetically sealed, glass envelope; electrodes sealed in the ends of said envelope; an arc generating and sustaining medium including mercury within said envelope for producing a plasma discharge when a predetermined voltage is applied across said electrodes; a phosphor coating adhering to the interior surface of said envelope; and a non-particulate film overlying said phosphor wherein said film comprises yttrium oxide and at least one U.V. absorber, said absorber being effective in the absorption of a greater amount of 185 nm radiation than 254 nm radiation from said plasma discharge.
Claim 3
Dependent Claim
14 words
The lamp of claim 1 wherein said phosphor is an alkaline earth halophosphate phosphor.
Claim 4
Dependent Claim
20 words
The lamp of claim 1 wherein said film has a thickness of from about 50 angstroms to about 500 angstroms.
Claim 5
Dependent Claim
11 words
The lamp of claim 1 wherein said U.V. absorber comprises europium.
Claim 6
Dependent Claim
11 words
The lamp of claim 1 wherein said U.V. absorber comprises manganese.
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) | 1989-08-18 | 1990-02-17 | 1990-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-08-18 | 1994-02-17 | 1994-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-08-18 | 1998-02-17 | 1998-08-19 | $7700.00 | Window Closed / Lapsed |