US3699383A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flow-through hollow cathode spectral light source and method of operating same
Assignee: HP Inc
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Filing: 1970-12-28
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Granted: 1972-10-17
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Expires: 1990-12-28
Abstract
Abstract An atomic spectral lamp includes a demountable, hollow cathode, and a funnel-shaped anode adjacent to the cathode. A glow discharge plasma is established in the cathode cavity. Counterflow through the funnel-shaped anode prevents self absorption of light by atomic vapor. Gas flow through the hollow cathode at a predetermined velocity increases the intensity of light-emitted from the plasma.
Inventors
- 👤 Robert L Chaney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:07
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/04; H01J61/06; H01J61/09; H05; H05H; H05H1/00; H05H1/24; H05H1/46; H05H1/4645; H05H1/466
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
210 words
An atomic spectral light source comprising: a vacuum chamber having a window portion and a vacuum port; a hollow cathode element having an open cavity therein disposed in said chamber in optical alignment with said window portion, said cathode element also having a gas passageway therethrough communicating with an internal portion of said cavity; means for producing a glow discharge plasma in said cavity; conduit means coupled to the gas passageway in said cathode element and having a gas inlet for directing a gas flow through the cavity of said cathode element at a predetermined velocity, thereby to permit optimization of the intensity of light emitted by said glow discharge plasma in said cavity; a member disposed between said cathode element and the window portion of said vacuum chamber, said member having an internal bore configured in the shape of a funnel having a narrow opening adjacent to said cathode element and a wide opening adjacent to said window portion; and gas inlet and conduit means for directing a flow of inert gas into the wide opening of said funnel adjacent to said window portion, thereby to cause gas flow through said funnel in a direction opposite to that of the radiation out of said cavity toward said window portion.
Claim 2
Dependent Claim
210 words
An atomic spectral light source comprising: a vacuum chamber having a window portion and a vacuum port; a hollow cathode element having an open cavity therein disposed in said chamber in optical alignment with said window portion, said cathode element also having a gas passageway therethrough communicating with an internal portion of said cavity; means for producing a glow discharge plasma in said cavity; conduit means coupled to the gas passageway in said cathode element and having a gas inlet for directing a gas flow through the cavity of said cathode element at a predetermined velocity, thereby to permit optimization of the intensity of light emitted by said glow discharge plasma in said cavity; a member disposed between said cathode element and the window portion of said vacuum chamber, said member having an internal bore configured in the shape of a funnel having a narrow opening adjacent to said cathode element and a wide opening adjacent to said window portion; and gas inlet and conduit means for directing a flow of inert gas into the wide opening of said funnel adjacent to said window portion, thereby to cause gas flow through said funnel in a direction opposite to that of the radiation out of said cavity toward said window portion.
Claim 3
Dependent Claim
53 words
The apparatus of claim 1 wherein the cross-sectional area of said gas passageway in said cavity member is less than that of said conduit means to cause a decreasing gas pressure differential from said conduit means to said gas passageway, thereby to prevent formation of a glow discharge plasma in said conduit means.
Claim 4
Dependent Claim
24 words
The apparatus of claim 1, further including means for controlling the flow velocity of gas which is passed throUgh said passageway into said cavity.
Claim 5
Dependent Claim
26 words
The apparatus of claim 1, wherein the gas flow through said gas passageway is at the velocity of at least 6.0 X 105 centimeters per second.
Claim 6
Dependent Claim
35 words
The apparatus of claim 4, wherein the gas flow velocity through said gas passageway is in one of the ranges of 6.0 to 6.5 X 105 and 8.5 to 10 X 105 centimeters per second.
Claim 7
Dependent Claim
28 words
The apparatus of claim 4, wherein the gas directed through said cavity is an inert gas selected from the group consisting of helium, neon, argon, krypton and xenon.
Claim 8
Dependent Claim
52 words
The apparatus of claim 1, wherein said means for producing a glow discharge plasma in said cavity includes: an anode element in said vacuum chamber disposed in spaced-apart relation with said cathode element; and means for applying a positive potential to said anode element and a negative potential to said cathode element.
Claim 9
Dependent Claim
43 words
The apparatus of claim 1, wherein said member serves as an anode element and said means for producing a glow discharge plasma in said cavity includes means for applying a positive potential to said member and a negative potential to said cathode element.
Claim 10
Dependent Claim
200 words
In an atomic spectral light source including the combination of a vacuum chamber having a window portion and a vacuum port; a hollow cathode element disposed in said chamber so that the open portion of the cavity in said element is optically aligned with said window portion; a member disposed between said cathode element and said window portion having an internal bore configured in the shape of a funnel having a narrow opening adjacent to said cathode element and a wide opening adjacent to said window portion; and means for producing a glow discharge plasma in said cavity; a method for increasing the intensity of light emitted from said glow discharge plasma comprising: passing an inert gas through a gas passageway in said hollow cathode element into an internal portion of said cavity and out through the open portion of said cavity at a predetermined velocity of flow through said passageway while maintaining a predetermined pressure in said vacuum chamber, and directing a flow of inert gas into the wide opening of said funnel member, thereby to cause gas flow through said funnel in a direction opposite to that of the radiation out of said cavity toward said window portion.
Claim 11
Dependent Claim
200 words
In an atomic spectral light source including the combination of a vacuum chamber having a window portion and a vacuum port; a hollow cathode element disposed in said chamber so that the open portion of the cavity in said element is optically aligned with said window portion; a member disposed between said cathode element and said window portion having an internal bore configured in the shape of a funnel having a narrow opening adjacent to said cathode element and a wide opening adjacent to said window portion; and means for producing a glow discharge plasma in said cavity; a method for increasing the intensity of light emitted from said glow discharge plasma comprising: passing an inert gas through a gas passageway in said hollow cathode element into an internal portion of said cavity and out through the open portion of said cavity at a predetermined velocity of flow through said passageway while maintaining a predetermined pressure in said vacuum chamber, and directing a flow of inert gas into the wide opening of said funnel member, thereby to cause gas flow through said funnel in a direction opposite to that of the radiation out of said cavity toward said window portion.
Claim 12
Dependent Claim
22 words
The method of claim 9, wherein said flow velocity in said gas passageway is at least 6.0 X 105 centimeters per second.
Claim 13
Dependent Claim
30 words
The method of claim 10, wherein said flow velocity is in one of the ranges of 6.0 to 6.5 X 105 and 8.5 to 10.0 X 105 centimeters per second.
Claim 14
Dependent Claim
22 words
The method of claim 9, wherein said inert gas is selected from the group consisting of helium, neon, argon, krypton and xenon.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |