US3870882A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Esca x-ray source
Assignee: GCA Corp
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Filing: 1973-05-23
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Granted: 1975-03-11
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Expires: 1993-05-23
Abstract
Abstract The X-ray source disclosed herein provides essentially monochromatic X-rays for sample irradiation in electron spectroscopic apparatus. The X-rays are generated by the impingement of a high energy electron beam on a gas under substantial pressure, pumping being provided to maintain a vacuum at the electron beam source in the presence of escaping target gas.
Inventors
- 👤 Paul E Larson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:58
CPC Classifications
H; H01; H01J; H01J49/00; H01J49/44; H01J49/46; H01J49/48; H01J49/484; H01J35/00; H01J35/02; H01J35/16; H01J35/18
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
170 words
An electron spectrometer comprising: means for holding a sample which is to be analyzed; means for analyzing photoelectrons given off by said sample as a function of their energies thereby to obtain an energy spectrum; housing means defining an X-ray target chamber; means for providing neon gas to said chamber at substantial pressure, said housing means also defining a chamber separate from said target chamber, there being a small aperture between said chambers; in said separate chamber, an electron gun for directing, through said small aperture a narrow beam of electrons into said target chamber at an energy level above that required to excite the neon K Alpha emission line; means for pumping the electron gun chamber to maintain a vacuum in the presence of gas flow through said aperture; and an X-ray window in said target chamber allowing X-rays comprising mainly the K Alpha neon emission line to essentially directly irradiate said sample without intervening dispersive selection thereby to obtain from said analyzing means a spectrum of improved resolution.
Claim 2
Dependent Claim
170 words
An electron spectrometer comprising: means for holding a sample which is to be analyzed; means for analyzing photoelectrons given off by said sample as a function of their energies thereby to obtain an energy spectrum; housing means defining an X-ray target chamber; means for providing neon gas to said chamber at substantial pressure, said housing means also defining a chamber separate from said target chamber, there being a small aperture between said chambers; in said separate chamber, an electron gun for directing, through said small aperture a narrow beam of electrons into said target chamber at an energy level above that required to excite the neon K Alpha emission line; means for pumping the electron gun chamber to maintain a vacuum in the presence of gas flow through said aperture; and an X-ray window in said target chamber allowing X-rays comprising mainly the K Alpha neon emission line to essentially directly irradiate said sample without intervening dispersive selection thereby to obtain from said analyzing means a spectrum of improved resolution.
Claim 3
Dependent Claim
170 words
An electron spectrometer comprising: means for holding a sample which is to be analyzed; means for analyzing photoelectrons given off by said sample as a function of their energies thereby to obtain an energy spectrum; housing means defining an X-ray target chamber; means for providing neon gas to said chamber at substantial pressure, said housing means also defining a chamber separate from said target chamber, there being a small aperture between said chambers; in said separate chamber, an electron gun for directing, through said small aperture a narrow beam of electrons into said target chamber at an energy level above that required to excite the neon K Alpha emission line; means for pumping the electron gun chamber to maintain a vacuum in the presence of gas flow through said aperture; and an X-ray window in said target chamber allowing X-rays comprising mainly the K Alpha neon emission line to essentially directly irradiate said sample without intervening dispersive selection thereby to obtain from said analyzing means a spectrum of improved resolution.
Claim 4
Dependent Claim
170 words
An electron spectrometer comprising: means for holding a sample which is to be analyzed; means for analyzing photoelectrons given off by said sample as a function of their energies thereby to obtain an energy spectrum; housing means defining an X-ray target chamber; means for providing neon gas to said chamber at substantial pressure, said housing means also defining a chamber separate from said target chamber, there being a small aperture between said chambers; in said separate chamber, an electron gun for directing, through said small aperture a narrow beam of electrons into said target chamber at an energy level above that required to excite the neon K Alpha emission line; means for pumping the electron gun chamber to maintain a vacuum in the presence of gas flow through said aperture; and an X-ray window in said target chamber allowing X-rays comprising mainly the K Alpha neon emission line to essentially directly irradiate said sample without intervening dispersive selection thereby to obtain from said analyzing means a spectrum of improved resolution.
Claim 5
Dependent Claim
23 words
Apparatus as set forth in claim 1 wherein said neon gas is provided at a pressure of about 10 2 - 100 atmospheres.
Claim 6
Dependent Claim
19 words
Apparatus as set forth in claim 1 wherein one end of said target chamber comprises a water-cooled electron trap.
Claim 7
Dependent Claim
30 words
Apparatus as set forth in claim 1 wherein each end of said differential pumping chamber comprises a diaphragm-like member having one of said small apertures formed by said electron gun.
Claim 8
Dependent Claim
12 words
Apparatus as set forth in claim 1 wherein said window is aluminum.
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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) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |