Patent US4476413A successfully refreshed from Google Patents.
US4476413A
Expired / Lapsed
US
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Atomic spectral lamp
Assignee: Commonwealth Scientific and Industrial Research Organisation
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Filing: 1981-03-13
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Granted: 1984-10-09
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Expires: 2001-03-13
Abstract
Abstract An atomic spectral lamp of the type comprising a predominantly glass envelope in which are disposed spaced electrodes for producing an electrical discharge on application of a suitable potential difference thereto and a substance which, on being heated will yield a vapor of an element capable of emitting the resonance line or lines which characterize the lamp. In normal operation of the lamp, there exists between the anode and the cathode a temperature gradient effective to ensure that the vapor pressure of the elemental vapor adjacent the cathode is small relative to the vapor pressure of the elemental vapor in the vicinity of said substance. In another aspect, heating means is provided for heating the substance independently of the discharge to yield the elemental vapor within the envelope.
Inventors
- 👤 David S. Gough
- 👤 John V. Sullivan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:35
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/70
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
158 words
An atomic spectral lamp of the type comprising a predominantly glass envelope in which are disposed spaced electrodes including a single anode and a single electron emitter filament cathode for producing an electrical discharge on application of a suitable potential difference to the electrodes and a substance that on being heated will yield a vapour of an element which characterizes the lamp and which is detrimental to the electron emitting capacity of said cathode, wherein said substance is so positioned that said vapour flows into the path of said discharge at a position spaced from said cathode, and wherein said envelope is provided with structural means so that in normal operation of the lamp, when said substance is heated there exists within the envelope a temperature gradient effective to ensure that the vapour pressure of the elemental vapour in the vicinity of the cathode is small relative to the vapour pressure of the elemental vapour at said position.
Claim 2
Dependent Claim
158 words
An atomic spectral lamp of the type comprising a predominantly glass envelope in which are disposed spaced electrodes including a single anode and a single electron emitter filament cathode for producing an electrical discharge on application of a suitable potential difference to the electrodes and a substance that on being heated will yield a vapour of an element which characterizes the lamp and which is detrimental to the electron emitting capacity of said cathode, wherein said substance is so positioned that said vapour flows into the path of said discharge at a position spaced from said cathode, and wherein said envelope is provided with structural means so that in normal operation of the lamp, when said substance is heated there exists within the envelope a temperature gradient effective to ensure that the vapour pressure of the elemental vapour in the vicinity of the cathode is small relative to the vapour pressure of the elemental vapour at said position.
Claim 3
Dependent Claim
24 words
An atomic spectral lamp according to claim 1 wherein the envelope is generally tubular with the electrodes positioned at or near opposite ends thereof.
Claim 4
Dependent Claim
32 words
An atomic spectral lamp according to claim 2, wherein the envelope includes a constriction spaced from said cathode to increase current density in said discharge path and to define a viewing window.
Claim 5
Dependent Claim
19 words
An atomic spectral lamp according to claim 1, 2 or 3 wherein said substance is disposed about the anode.
Claim 6
Dependent Claim
33 words
An atomic spectral lamp according to claim 1, 2 or 3 wherein the anode is spaced from said substance at a location between the substance and the cathode and closer to said substance.
Claim 7
Dependent Claim
33 words
An atomic spectral lamp according to claim 1, 2 or 3 further including heating means for heating said substance independently of said discharge to yield a vapour of said element within the envelope.
Claim 8
Dependent Claim
23 words
An atomic spectral lamp according to claim 6 wherein the heating means is an ohmic resistance winding about a part of said envelope.
Claim 9
Dependent Claim
27 words
An atomic spectral lamp according to claim 1, 2 or 3 wherein said structural means of said envelope includes a relatively enlarged bulbous portion adjacent the cathode.
Claim 10
Dependent Claim
25 words
An atomic spectral lamp according to claim 6 wherein the anode is spaced from said substance at a location between the substance and the cathode.
Claim 11
Dependent Claim
30 words
An atomic spectral lamp according to claim 9 further including heating means for heating said substance independently of said discharge to yield a vapour of said element within the envelope.
Claim 12
Dependent Claim
26 words
An atomic spectral lamp according to claim 1 wherein the substance will, on being heated, yield a vapour of one of arsenic, selenium, sulphur and phosphorous.
Claim 13
Dependent Claim
19 words
An atomic spectral lamp according to claim 1, 2 or 3 wherein said filament cathode is a coated filament.
References Cited (Backward Citations)
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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) | 1987-10-09 | 1988-04-09 | 1988-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-09 | 1992-04-09 | 1992-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-09 | 1996-04-09 | 1996-10-09 | $7700.00 | Window Closed / Lapsed |