US4710679A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorescent light source excited by excimer emission
Assignee: Osram Sylvania Inc
•
Filing: 1985-12-06
•
Granted: 1987-12-01
•
Expires: 2005-12-06
Abstract
Abstract A fluorescent lamp is described in which spontaneous excimer UV emission in an inner tube results from reacting an inert gas molecule with a halide molecule in the excited state. The UV emission travels through the inner tube envelope to an outer tube and is absorbed by a fluorescent material, i.e., phosphor, to produce visible light which passes through the outer tube envelope. The halide may be supplied by metal halide pellets or liquid droplets, which when heated by an initial discharge through an inert gas, produces metal halide vapors which dissociate and combine with the inert gas (Xe, Ar, Ne, Kr) in the excited state and result in UV excimer emission.
Inventors
- 👤 A. Bowman Budinger
- 👤 Walter P. Lapatovich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:55
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/70; H01J61/02; H01J61/12; H01J61/125
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
124 words
A light source comprising: (a) a visible light transparent outer envelope containing fluorescent means for emitting visible light radiation upon absorption of UV emission; and (b) UV emission means for providing UV excimer emission within a separate inner envelope within said outer envelope for transmission through said separate inner envelope and absorption by said fluorescent means to produce visible illumination for passage through said outer envelope; said UV emission means comprising a metal halide and a buffer gas and an electrode means for creating an electrical discharge which excites the buffer gas and dissociates the metal halide and wherein molecules of said halide combine with molecules of the excited gas to produce an excimer, which upon decay, results in spontaneous emission of UV light.
Claim 2
Dependent Claim
124 words
A light source comprising: (a) a visible light transparent outer envelope containing fluorescent means for emitting visible light radiation upon absorption of UV emission; and (b) UV emission means for providing UV excimer emission within a separate inner envelope within said outer envelope for transmission through said separate inner envelope and absorption by said fluorescent means to produce visible illumination for passage through said outer envelope; said UV emission means comprising a metal halide and a buffer gas and an electrode means for creating an electrical discharge which excites the buffer gas and dissociates the metal halide and wherein molecules of said halide combine with molecules of the excited gas to produce an excimer, which upon decay, results in spontaneous emission of UV light.
Claim 3
Dependent Claim
26 words
The source of claim 1 wherein the metal halide is in the form of a solid or liquid which is heated to the point of vaporization.
Claim 4
Dependent Claim
29 words
The source of claim 2 wherein the metal halide is a compound taken from the class comprising AlCl 3 , HgCl 2 , SnCl 4 and GaCl 3 .
Claim 5
Dependent Claim
142 words
A source of visible illumination comprising: (a) ultraviolet emission means within a first envelope for generating spontaneous excimer ultraviolet emission from an electrical discharge between two electrodes in an enclosed atmosphere of metal halide vapors and an inert gas; and (b) visible emission means in a second envelope about said first envelope responsive to said ultraviolet emission for generating visible light and wherein a ballast circuit is coupled across said electrodes for providing a current flow through said electrodes to emit sufficient electrons to cause an electrical discharge through a buffer gas, bringing the buffer gas molecule to its excited state and heating an inner chamber to cause the metal halide to form metal halide vapors and wherein the metal halide is dissociated, and halide molecules combine with the excited state buffer gas molecules whereupon spontaneous excimer radiation at UV wavelength occurs.
Claim 6
Dependent Claim
142 words
A source of visible illumination comprising: (a) ultraviolet emission means within a first envelope for generating spontaneous excimer ultraviolet emission from an electrical discharge between two electrodes in an enclosed atmosphere of metal halide vapors and an inert gas; and (b) visible emission means in a second envelope about said first envelope responsive to said ultraviolet emission for generating visible light and wherein a ballast circuit is coupled across said electrodes for providing a current flow through said electrodes to emit sufficient electrons to cause an electrical discharge through a buffer gas, bringing the buffer gas molecule to its excited state and heating an inner chamber to cause the metal halide to form metal halide vapors and wherein the metal halide is dissociated, and halide molecules combine with the excited state buffer gas molecules whereupon spontaneous excimer radiation at UV wavelength occurs.
Claim 7
Dependent Claim
40 words
The source of claim 4 wherein the visible emission means comprises: (i) an outer envelope transparent to visible radiation surrounding said inner envelope and containing either phosphour material or iodine vapor for generating visible light in response to UV emission.
Claim 8
Dependent Claim
41 words
The source of claim 5 wherein the ballast circuit comprises a pair of switches in the circuit path of the two filamentary electrodes and the current flow, one of which is opened after initial discharge in the inner chamber is established.
Claim 9
Dependent Claim
15 words
The source of claim 4 in which the electrodes are formed of thorium and iridium.
Claim 10
Dependent Claim
28 words
The source of claim 4 in which the metal halide is taken from the class comprising AlCL 3 , HgCl 2 , SnCl 4 and GaCl 3 .
Claim 11
Dependent Claim
18 words
The source of claim 5 wherein the material is a solid phosphor coated on the outer envelope wall.
Claim 12
Dependent Claim
13 words
The source of claim 5 wherein the material is a light emitting gas.
Claim 13
Dependent Claim
29 words
The source of claim 4 wherein the metal halide is AlCl 3 , the inert gas is Xenon, and the peak emission has a wavelength of about 300 nanometers.
Claim 14
Dependent Claim
29 words
The source of claim 4 wherein the metal halide is AlCl 3 , the inert gas is Krypton, and the peak emission has a wavelength of about 202 nanometers.
References Cited (Backward Citations)
US3581137A
Cited
US3586898A
Cited
US4490642A
Cited
US4427924A
Cited
US4549109A
Cited
US4480213A
Cited
US4492898A
Cited
US4510418A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-11-30 | 1991-06-01 | 1991-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-30 | 1995-06-01 | 1995-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-30 | 1999-06-01 | 1999-12-01 | $7700.00 | Window Closed / Lapsed |