US4670688A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorescent lamp with improved lumen output
Assignee: Osram Sylvania Inc
•
Filing: 1981-12-24
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Granted: 1987-06-02
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Expires: 2001-12-24
Abstract
Abstract The lumen output of a fluorescent lamp is improved by the triode radio frequency sputter coating of a continuous protective coating of vitreous alumina overlying the lamp phosphor layer.
Inventors
- 👤 A. Gary Sigai
- 👤 John M. Flaherty
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:54
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/38; H01J61/42
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
53 words
In a fluorescent lamp having a light transparent envelope containing an ionizable medium which includes mercury vapor and which includes electrodes sealed into the ends thereof and a layer of phosphor on the interior surface of said envelope, the improvement comprising: a continuous protective coating of vitreous alumina overlying said layer of phosphor.
Claim 2
Dependent Claim
53 words
In a fluorescent lamp having a light transparent envelope containing an ionizable medium which includes mercury vapor and which includes electrodes sealed into the ends thereof and a layer of phosphor on the interior surface of said envelope, the improvement comprising: a continuous protective coating of vitreous alumina overlying said layer of phosphor.
Claim 3
Dependent Claim
19 words
A lamp according to claim 1 wherein said layer of vitreous alumina is less than about 500 angstroms thick.
Claim 4
Dependent Claim
28 words
A lamp according to claim 1 wherein said layer of vitreous alumina preferentially absorbs short wavelength ultraviolet radiation and transmits longer wavelength ultraviolet radiation 254 nanometers and greater.
Claim 5
Dependent Claim
16 words
A lamp according to claim 1 wherein said continuous protective coating is sputter coated vitreous alumina.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-01 | 1990-12-01 | 1991-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-01 | 1994-12-01 | 1995-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-01 | 1998-12-01 | 1999-06-02 | $7700.00 | Window Closed / Lapsed |