Patent US3979590A successfully refreshed from Google Patents.
US3979590A
Expired / Lapsed
US
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Electron microscope comprising an energy analyzer
Assignee: US Philips Corp
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Filing: 1975-03-28
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Granted: 1976-09-07
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Expires: 1995-03-28
Abstract
Abstract A Wien filter, used as an energy analyzer in an electron microscope, includes a four-pole lens which enlarges the dispersion of electrons in one direction. By addition of six-pole lenses and an additional four-pole lens, correction can be made for opening errors in the electron beam to be analyzed.
Inventors
- 👤 Willem Hendrik Jan Andersen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:55
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/02; H01J37/04; H01J37/05; H01J37/153
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
119 words
An electron microscope comprising an electron source, electron-optical lens system to form an electron beam having a cross-over section, a dispersing energy analyzer including a Wien filter for which the cross-over section acts as an object, said filter being operable for dispersing in a transverse direction with respect to the axial direction of the beam the electrons having velocities deviating from a preselected velocity; a four-pole lens system located at the output of said filter to increase the dispersion in said transverse direction, deflection means for moving the beam in said transverse direction, an output screen located in an image plane and having an elongate slot extending in said transverse direction, and an electron detector located behind the slot.
Claim 2
Dependent Claim
119 words
An electron microscope comprising an electron source, electron-optical lens system to form an electron beam having a cross-over section, a dispersing energy analyzer including a Wien filter for which the cross-over section acts as an object, said filter being operable for dispersing in a transverse direction with respect to the axial direction of the beam the electrons having velocities deviating from a preselected velocity; a four-pole lens system located at the output of said filter to increase the dispersion in said transverse direction, deflection means for moving the beam in said transverse direction, an output screen located in an image plane and having an elongate slot extending in said transverse direction, and an electron detector located behind the slot.
Claim 3
Dependent Claim
34 words
An electron microscope as claimed in claim 1, wherein a six-pole lens correction system is arranged between the four-pole lens system and the output screen, for correcting second-order beam opening errors of the analyser.
Claim 4
Dependent Claim
36 words
An electron microscope as claimed in claim 1, wherein the analyser has an additional four-pole lens for an independent correction of errors in the imaging due to a deviating energy selection setting of the energy analyser.
Claim 5
Dependent Claim
29 words
An electron microscope as claimed in claim 1, further comprising an additional deflection device for moving the beam in a direction perpendicular to the longitudinal dimension of said slot.
Claim 6
Dependent Claim
37 words
An electron microscope as claimed in claim 1, further including an intermediate image screen which acts as an entrance pupil for the analyser and has a passage opening in the range of approximately 0.05 to 2 mm.
References Cited (Backward Citations)
US3256433A
Cited
GB1364930A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-07 | 1980-03-08 | 1980-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-07 | 1984-03-08 | 1984-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-07 | 1988-03-08 | 1988-09-07 | $7700.00 | Window Closed / Lapsed |