Patent US4429228A successfully refreshed from Google Patents.
US4429228A
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US
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High efficiency photoionization detector
Assignee: United States Department of Energy
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Filing: 1981-05-12
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Granted: 1984-01-31
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Expires: 2001-05-12
Abstract
Abstract A high efficiency photoionization detector using tetraaminoethylenes in a gaseous state having a low ionization potential and a relative photoionization cross section which closely matches the emission spectrum of xenon gas. Imaging proportional counters are also disclosed using the novel photoionization detector of the invention. The compound of greatest interest is TMAE which comprises tetrakis(dimethylamino)ethylene which has a measured ionization potential of 5.36+/-0.02 eV, and a vapor pressure of 0.35 torr at 20 DEG C.
Inventors
- 👤 David F. Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:47
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/16; G01T1/20; G01T1/205; G01T1/29; G01T1/2914; G01T1/2921; G01T1/2935
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
19 words
A detection gas for use in a photoionization detector comprising: a tetraaminoethylene having an ionization potential below 6.22 eV.
Claim 2
Dependent Claim
19 words
A detection gas for use in a photoionization detector comprising: a tetraaminoethylene having an ionization potential below 6.22 eV.
Claim 3
Dependent Claim
15 words
The detection gas of claim 1 wherein said tetraaminoethylene comprises at least in part tetrakis(dimethylamino)ethylene.
Claim 4
Dependent Claim
15 words
The detection gas of claim 1 wherein said tetraaminoethylene comprises at least in part 1,1',3,3'-tetramethyl-2,2'-biimidazolidinylidene.
Claim 5
Dependent Claim
15 words
The detection gas of claim 1 wherein said tetraaminoethylene comprises at least in part 1,1,4,4-tetrakis(dimethylamino)butadiene.
Claim 6
Dependent Claim
15 words
The detection gas of claim 1 wherein said tetraaminoethylene comprises at least in part N,N,N',N'-tetramethyl-p-phenylenediamine.
Claim 7
Dependent Claim
20 words
In a photoionization detector for converting incident ultraviolet photons to electrons, a detecting gas comprising at least in part: tetrakis(dimethylamino)ethylene.
Claim 8
Dependent Claim
20 words
In a photoionization detector for converting incident ultraviolet photons to electrons, a detecting gas comprising at least in part: tetrakis(dimethylamino)ethylene.
Claim 9
Dependent Claim
27 words
In an imaging photoionization detector for converting ultraviolet photons generated by a gas scintillation proportional counter to electrons, a detector gas comprising at least in part: tetrakis(dimethylamino)ethylene.
Claim 10
Dependent Claim
27 words
In an imaging photoionization detector for converting ultraviolet photons generated by a gas scintillation proportional counter to electrons, a detector gas comprising at least in part: tetrakis(dimethylamino)ethylene.
Claim 11
Independent Claim
56 words
A device for detecting x-rays comprising: gas scintillation proportional counter means for generating ultraviolet photons in response to said x-rays; photoionization detector means disposed proximate to said gas scintillation proportional counter for converting said ultraviolet photons generated by said gas scintillation proportional counter to electrons using a detection gas comprising at least in part tetrakis(dimethylamino) ethylene.
Claim 12
Independent Claim
56 words
A device for detecting x-rays comprising: gas scintillation proportional counter means for generating ultraviolet photons in response to said x-rays; photoionization detector means disposed proximate to said gas scintillation proportional counter for converting said ultraviolet photons generated by said gas scintillation proportional counter to electrons using a detection gas comprising at least in part tetrakis(dimethylamino) ethylene.
Claim 13
Independent Claim
102 words
A device for generating an electrical signal representative of an image of a source of x-rays comprising: an x-ray imaging device; gas scintillation proportional counter means for generating ultraviolet photons in response to x-rays imaged by said x-ray imaging device, said gas scintillation proportional counter means disposed at the focal plane of said x-ray imaging device; imaging photoionization detector means for converting said ultraviolet photons to an electrical signal representative of an image of said source of x-rays using a detection gas comprising at least in part tetrakis(dimethylamino)ethylene, said imaging proportional counter means disposed proximate to said gas scintillation proportional counter means.
Claim 14
Independent Claim
102 words
A device for generating an electrical signal representative of an image of a source of x-rays comprising: an x-ray imaging device; gas scintillation proportional counter means for generating ultraviolet photons in response to x-rays imaged by said x-ray imaging device, said gas scintillation proportional counter means disposed at the focal plane of said x-ray imaging device; imaging photoionization detector means for converting said ultraviolet photons to an electrical signal representative of an image of said source of x-rays using a detection gas comprising at least in part tetrakis(dimethylamino)ethylene, said imaging proportional counter means disposed proximate to said gas scintillation proportional counter means.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-30 | 1987-08-01 | 1988-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-30 | 1991-08-01 | 1992-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-30 | 1995-08-01 | 1996-01-31 | $7700.00 | Window Closed / Lapsed |