US4866328A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric lamp with reduced internal photoelectron production
Assignee: Philips North America LLC
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Filing: 1988-04-15
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Granted: 1989-09-12
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Expires: 2008-04-15
Abstract
Abstract An HID lamp having parts of its internal metal support covered with a layer of material having a photoelectric work function greater than 5.0 electron volts to reduce internal photoelectron production. The material may be granular zirconium oxide having a photoelectric work function of 5.8 eV.
Inventors
- 👤 Raghu Ramaiah
- 👤 Daniel H. Shumway
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:10
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/30; H01J61/34
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
70 words
In an electric lamp having an outer envelope and a light source that emits ultraviolet radiation, the improvement comprising: a metallic frame for mounting said light source within said outer envelope; and a layer of ZrO 2 covering a substantial portion of said frame and being effective to shield said substantial portion of said frame from ultraviolet radiation emitted by said light source to reduce photoelectron emission from said frame.
Claim 2
Dependent Claim
70 words
In an electric lamp having an outer envelope and a light source that emits ultraviolet radiation, the improvement comprising: a metallic frame for mounting said light source within said outer envelope; and a layer of ZrO 2 covering a substantial portion of said frame and being effective to shield said substantial portion of said frame from ultraviolet radiation emitted by said light source to reduce photoelectron emission from said frame.
Claim 3
Dependent Claim
21 words
In an electric lamp according to claim 1, wherein said layer of ZrO 2 is comprised of granular ZrO 2 .
Claim 4
Dependent Claim
109 words
In an electric lamp having an outer envelope and a light source that emits ultraviolet radiation, the improvement comprising: said outer envelope having an outwardly bulged bulbous shape; a metallic frame for mounting said light source within said outer envelope, said metallic mounting frame comprising a bent rod extending along the length of said length envelope, away form said light source and adjacent said outer envelope to maximize the distance between said metallic frame and said light source; and a layer of material disposed on and covering a substantial portion of said bent rod and being effective to shield said substantial portion of said bent rod from ultraviolet radiation.
Claim 5
Dependent Claim
109 words
In an electric lamp having an outer envelope and a light source that emits ultraviolet radiation, the improvement comprising: said outer envelope having an outwardly bulged bulbous shape; a metallic frame for mounting said light source within said outer envelope, said metallic mounting frame comprising a bent rod extending along the length of said length envelope, away form said light source and adjacent said outer envelope to maximize the distance between said metallic frame and said light source; and a layer of material disposed on and covering a substantial portion of said bent rod and being effective to shield said substantial portion of said bent rod from ultraviolet radiation.
Claim 6
Dependent Claim
17 words
In an electric lamp according to claim 3, wherein said layer is comprised of ZrO 2 .
Claim 7
Dependent Claim
21 words
In an electric lamp according to claim 4, wherein said layer of ZrO 2 is comprised of granular ZrO 2 .
Claim 8
Dependent Claim
23 words
In an electric lamp according to claim 3, said layer of material having a photoelectric work function greater than about 5.0 electron volts.
Claim 9
Dependent Claim
27 words
In an electric lamp according to claim 6, wherein said layer is comprised of ZrO 2 and has a photoelectric work function of about 5.8 electron volts.
Claim 10
Dependent Claim
68 words
In an electric discharge lamp: a discharge light source that emits ultraviolet radiation; mounting means comprising a nonlinear metallic support rod for mounting said discharge light source within the lamp; and a layer of material having a photoelectric work function greater than 5.0 electron volts disposed on and covering a substantial portion of said nonlinear metallic support rod for shielding said covered substantial portion from the ultraviolet radiation.
Claim 11
Dependent Claim
68 words
In an electric discharge lamp: a discharge light source that emits ultraviolet radiation; mounting means comprising a nonlinear metallic support rod for mounting said discharge light source within the lamp; and a layer of material having a photoelectric work function greater than 5.0 electron volts disposed on and covering a substantial portion of said nonlinear metallic support rod for shielding said covered substantial portion from the ultraviolet radiation.
Claim 12
Dependent Claim
27 words
In an electric discharge lamp according to claim 8; said layer of material having a photoelectric work function greater than 5.0 electron volts comprising ZrO 2 .
References Cited (Backward Citations)
US3484637A
Cited
US3780331A
Cited
US3988628A
Cited
US4006378A
Cited
US4171498A
Cited
US4469980A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-09-11 | 1993-03-13 | 1993-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-11 | 1997-03-13 | 1997-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-11 | 2001-03-13 | 2001-09-12 | $7700.00 | Window Closed / Lapsed |