US5032762A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Protective beryllium oxide coating for high-intensity discharge lamps
Assignee: General Electric Co
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Filing: 1990-07-16
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Granted: 1991-07-16
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Expires: 2010-07-16
Abstract
Abstract A protective beryllium oxide coating of suitable thickness is applied to the inner surface of the arc tube of a high-intensity, metal halide discharge lamp in order to avoid a substantial loss of the metallic portion of the metal halide fill and hence a substantial buildup of free halogen, thereby extending the useful life of the lamp. A preferred lamp structure includes a fused silica arc tube. The beryllium oxide coating is preferably applied to the arc tube by evaporating beryllium in the arc tube under non-oxidizing conditions, and then heating in an oxidizing atmosphere.
Inventors
- 👤 Henry S. Spacil
- 👤 Ronald H. Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:41
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/30; H01J61/35; H01J61/24
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
88 words
A high intensity discharge lamp, comprising: a light-transmissive arc tube for containing a plasma arc discharge; a fill disposed in said arc tube, said fill including at least one metal halide; excitation means for coupling electrical power to said fill for exciting said arc discharge therein; and a protective beryllium oxide coating disposed on the inner surface of said arc tube of sufficient thickness to prevent a substantial loss of the metallic portion of said fill and a corresponding substantial buildup of free halogen in said arc tube.
Claim 2
Dependent Claim
88 words
A high intensity discharge lamp, comprising: a light-transmissive arc tube for containing a plasma arc discharge; a fill disposed in said arc tube, said fill including at least one metal halide; excitation means for coupling electrical power to said fill for exciting said arc discharge therein; and a protective beryllium oxide coating disposed on the inner surface of said arc tube of sufficient thickness to prevent a substantial loss of the metallic portion of said fill and a corresponding substantial buildup of free halogen in said arc tube.
Claim 3
Dependent Claim
14 words
The lamp of claim 1 wherein said arc tube is comprised of fused silica.
Claim 4
Dependent Claim
24 words
The lamp of claim 1 wherein the thickness of said protective beryllium oxide coating is in the range from approximately 5 to 500 nanometers.
Claim 5
Dependent Claim
24 words
The lamp of claim 3 wherein the thickness of said protective beryllium oxide coating is in the range from approximately 50 to 200 nanometers.
Claim 6
Dependent Claim
101 words
An electrodeless high intensity discharge lamp, comprising: a light-transmissive arc tube for containing a plasma arc discharge; a fill disposed in said arc tube, said fill including at least one metal halide; an excitation coil disposed about said arc tube and adapted to be coupled to a radio frequency power supply for exciting said arc discharge in said fill; and a protective beryllium oxide coating disposed on the inner surface of said arc tube of sufficient thickness to prevent a substantial loss of the metallic portion of said fill and a corresponding substantial buildup of free halogen in said arc tube.
Claim 7
Dependent Claim
101 words
An electrodeless high intensity discharge lamp, comprising: a light-transmissive arc tube for containing a plasma arc discharge; a fill disposed in said arc tube, said fill including at least one metal halide; an excitation coil disposed about said arc tube and adapted to be coupled to a radio frequency power supply for exciting said arc discharge in said fill; and a protective beryllium oxide coating disposed on the inner surface of said arc tube of sufficient thickness to prevent a substantial loss of the metallic portion of said fill and a corresponding substantial buildup of free halogen in said arc tube.
Claim 8
Dependent Claim
14 words
The lamp of claim 5 wherein said arc tube is comprised of fused silica.
Claim 9
Dependent Claim
24 words
The lamp of claim 5 wherein the thickness of said protective beryllium oxide coating is in the range from approximately 5 to 500 nanometers.
Claim 10
Dependent Claim
24 words
The lamp of claim 7 wherein the thickness of said protective beryllium oxide coating is in the range from approximately 50 to 200 nanometers.
Claim 11
Independent Claim
63 words
A method for manufacturing an electrodeless, high-intensity, metal halide discharge lamp having an arc tube for containing a plasma arc discharge, comprising the steps of: applying a beryllium oxide coating to the inner surface of said arc tube; filling said arc tube with a fill including at least one metal halide; adding a buffer gas to said fill; and sealing said arc tube.
Claim 12
Independent Claim
63 words
A method for manufacturing an electrodeless, high-intensity, metal halide discharge lamp having an arc tube for containing a plasma arc discharge, comprising the steps of: applying a beryllium oxide coating to the inner surface of said arc tube; filling said arc tube with a fill including at least one metal halide; adding a buffer gas to said fill; and sealing said arc tube.
Claim 13
Dependent Claim
58 words
The method of claim 9 wherein said step of applying said beryllium oxide coating comprises: filling said arc tube with a predetermined quantity of beryllium; evaporating said beryllium under non-oxidizing conditions to form a layer thereof on the inner surface of said arc tube; and heating said beryllium in an oxidizing atmosphere to form said beryllium oxide coating.
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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) | 1994-07-15 | 1995-01-14 | 1995-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-15 | 1999-01-14 | 1999-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-15 | 2003-01-14 | 2003-07-16 | $7700.00 | Window Closed / Lapsed |