Patent US4468997A successfully refreshed from Google Patents.
US3710103A
Expired / Lapsed
US
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Planar retarding grid electron spectrometer
Assignee: Varian Medical Systems Inc
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Filing: 1971-12-03
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Granted: 1973-01-09
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Expires: 1991-12-03
Abstract
Abstract A retarding grid form of electron spectrometer utilizing a single grid structure, the retarding grid being planar and being positioned in a focusing structure that first defocuses the beam of electrons and then refocuses it onto an electron detector, the retarding grid being located in the focusing structure near the point of maximum diameter of the electron beam. The focusing structure produces very strong accelerating and decelerating fields near its beam entrance and exit regions, respectively, such that the retarding and accelerating fields at the retarding grid are very weak, resulting in sharp lines in the electron spectrum.
Inventors
- 👤 J Helmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:38
CPC Classifications
H; H01; H01J; H01J49/00; H01J49/44; H01J49/46; H01J49/48; H01J49/488
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
97 words
An electron spectrometer comprising means for inducing electron emission from a sample under analysis, an electron detector means for measuring electrons impinging thereon, a focusing means of rotational symmetry about a central axis for focusing electrons emitted from said sample onto said electron detector means, a grid positioned in the focusing means in a region of maximum electron beam diameter and lying substantially normal to the central axis through said focusing means, and means for applying a variable voltage to said grid relative to said sample to cause electrons of selective energies to impinge onto said detector.
Claim 2
Dependent Claim
97 words
An electron spectrometer comprising means for inducing electron emission from a sample under analysis, an electron detector means for measuring electrons impinging thereon, a focusing means of rotational symmetry about a central axis for focusing electrons emitted from said sample onto said electron detector means, a grid positioned in the focusing means in a region of maximum electron beam diameter and lying substantially normal to the central axis through said focusing means, and means for applying a variable voltage to said grid relative to said sample to cause electrons of selective energies to impinge onto said detector.
Claim 3
Dependent Claim
17 words
An electron spectrometer as claimed in claim 1 wherein said electron beam detector is an electron multiplier.
Claim 4
Dependent Claim
37 words
An electron beam spectrometer as claimed in claim 1 including a second electron beam focusing means positioned between said sample and said first focusing means for focusing the electrons from said sample into said first focusing means.
Claim 5
Dependent Claim
40 words
An electron spectrometer as claimed in claim 3 including a third electron beam focusing means positioned between said first focusing means and said electron detector means for focusing the electrons exiting from said first focusing means onto said electron detector.
Claim 6
Dependent Claim
23 words
An electron spectrometer as claimed in claim 1 wherein said focusing means is symmetrical in the central axial direction, said grid being planar.
Claim 7
Dependent Claim
25 words
An electron spectrometer as claimed in claim 5 wherein said grid is positioned at approximately the midpoint of the central axis through said focusing means.
Claim 8
Dependent Claim
55 words
An electron spectrometer as claimed in claim 5 wherein said focusing means comprises a plurality of annular electrodes spaced in axial alignment along said central axis, the inner diameters of the electrodes increasing in size from the electrodes on either end of the focusing means to the electrodes at the center of the focusing means.
Claim 9
Dependent Claim
68 words
An electron spectrometer as claimed in claim 1 including means for applying voltages to said focusing means to create a substantial electron decelerating field near the entrance end of said focusing means and a substantial accelerating field near the exit end of said focusing means, the decelerating and accelerating field at the grid being weak relative to the entrance decelerating and exit accelerating fields of said focusing means.
Claim 10
Dependent Claim
23 words
An electron spectrometer as claimed in claim 8 wherein said focusing means is symmetrical in the central axial direction, said grid being planar.
Claim 11
Dependent Claim
25 words
An electron spectrometer as claimed in claim 9 wherein said grid is positioned at approximately the midpoint of the central axis through said focusing means.
Claim 12
Dependent Claim
101 words
An electron spectrometer as claimed in claim 1 wherein saId focusing means comprises a first section positioned between the grid and said sample and including an entrance region for the electrons and a second region near the grid, and a second section positioned between the grid and said electron detector and including an exit region for the electrons and a second region near the grid, said focusing means creating electron decelerating and accelerating fields in said entrance and exit regions, respectively, substantially greater than the electron decelerating and accelerating fields in said second regions of said first and second sections, respectively.
Claim 13
Dependent Claim
43 words
An electron spectrometer as claimed in claim 11 wherein the fields in the entrance region and the second region of said first section are symmetrical with respect to the fields in the exit region and the second region of said second section, respectively.
Claim 14
Dependent Claim
33 words
An electron spectrometer as claimed in claim 11 wherein the decelerating and accelerating fields in said first and second regions are at least ninety percent greater than the fields in said second regions.
Claim 15
Dependent Claim
38 words
An electron spectrometer as claimed in claim 11 wherein said focusing means is symmetrical in the central axial direction, said grid being planar and being positioned at approximately the midpoint of the central axis through said focusing means.
Claim 16
Dependent Claim
91 words
An electron spectrometer comprising means for inducing electron emission from a sample under analysis, an electron detector means for measuring electrons impinging thereon, an electrostatic focusing means of rotational symmetry about a central axis for focusing electrons emitted from said sample onto said electron detector means, a planar grid positioned in the focusing means and lying substantially normal to the central axis through said focusing means, and means for applying a variable voltage to said grid relative to said sample to cause electrons of selective energies to impinge onto said detector.
Claim 17
Dependent Claim
91 words
An electron spectrometer comprising means for inducing electron emission from a sample under analysis, an electron detector means for measuring electrons impinging thereon, an electrostatic focusing means of rotational symmetry about a central axis for focusing electrons emitted from said sample onto said electron detector means, a planar grid positioned in the focusing means and lying substantially normal to the central axis through said focusing means, and means for applying a variable voltage to said grid relative to said sample to cause electrons of selective energies to impinge onto said detector.
Claim 18
Dependent Claim
56 words
An electron spectrometer as claimed in claim 15 wherein said electrostatic focusing means comprises a plurality of annular electrodes spaced in axial alignment along said central axis, the inner diameters of the electrodes increasing in size from the electrodes on either end of the focusing means to the electrodes at the center of the focusing means.
Claim 19
Dependent Claim
68 words
An electron spectrometer as claimed in claim 15 including means for applying voltages to said focusing means to create a substantial electron decelerating field near the entrance end of said focusing means and a substantial accelerating field near the exit end of said focusing means, the decelerating and accelerating field at the grid being weak relative to the entrance decelerating and exit accelerating fields of said focusing means.
Claim 20
Dependent Claim
36 words
An electron spectrometer as claimed in claim 17 wherein said focusing means is symmetrical in the central axial direction and said grid is positioned at approximately the midpoint of the central axis through said focusing means.
Claim 21
Dependent Claim
101 words
An electron spectrometer as claimed in claim 15 wherein said focusing means comprises a first section positioned between the grid and said sample and including an entrance region for the electrons and a second region near the grid, and a second section positioned between the grid and said electron detector and including an exit region for the electrons and a second region near the grid, said focusing means creating electron decelerating and accelerating fields in said entrance and exit regions, respectively, substantially greater than the electron decelerating and accelerating fields in said second regions of said first and second sections, respectively.
Claim 22
Dependent Claim
43 words
An electron spectrometer as claimed in claim 19 wherein the fields in the entrance region and the second region of said first section are symmetrical with respect to the fields in the exit region and the second region of said second section, respectively.
Claim 23
Dependent Claim
33 words
An electron spectrometer as claimed in claim 19 wherein the decelerating and accelerating fields in said first and second rEgions are at least ninety percent greater than the fields in said second regions.
Claim 24
Dependent Claim
35 words
An electron spectrometer as claimed in claim 19 wherein said focusing means is symmetrical in the central axial direction, said grid being positioned at approximately the midpoint of the central axis through said focusing 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) | 1976-01-09 | 1976-07-10 | 1977-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-09 | 1980-07-10 | 1981-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-09 | 1984-07-10 | 1985-01-09 | $7700.00 | Window Closed / Lapsed |