Patent US3671737A successfully refreshed from Google Patents.
US3671737A
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Method for focusing a double focusing mass spectrometer
Assignee: Bell and Howell Co
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Filing: 1969-05-07
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Granted: 1972-06-20
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Expires: 1989-05-07
Abstract
Abstract A double focusing mass spectrometer utilizing an electric and a magnetic analyzing sector in tandem provided with a mechanically adjustable magnetic sector. Optimum focusing of the instrument is obtained by translational and rotational adjustments of the magnetic sector.
Inventors
- 👤 Charles W Hull
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:12
CPC Classifications
H; H01; H01J; H01J49/00; H01J49/26; H01J49/28; H01J49/32
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
214 words
A method of focusing a tandem electric sector-magnetic sector double focusing mass spectrometer used for resolving a charged particle beam admitted into the spectrometer comprising the steps of: 1. determining a locus of centers of rotation of the magnetic sector, each of said centers having the characteristic that the location of the point of angular focus of the charged particle beam relative to the resolving point in the spectrometer is affected without affecting the location of the point of velocity focus of the charged particle beam relative to the resolving point when the magnetic sector is rotated thereabout, said locus of centers defining a substantially straight line substantially in the plane of the charged particle beam path; 2. moving the magnetic sector translationally in a direction parallel to said straight line and substantially in the plane of the charged particle beam path to locate the point of charged particle beam velocity focus at the resolving point of the spectrometer; and thereafter 3. moving the magnetic sector rotationally about a center of rotation lying on said straight line and substantially in the plane of the charged particle beam path to simultaneously locate the point of charged particle beam angular focus at the resolving point of the spectrometer whereby the spectrometer is put into optimum focus.
Claim 2
Independent Claim
214 words
A method of focusing a tandem electric sector-magnetic sector double focusing mass spectrometer used for resolving a charged particle beam admitted into the spectrometer comprising the steps of: 1. determining a locus of centers of rotation of the magnetic sector, each of said centers having the characteristic that the location of the point of angular focus of the charged particle beam relative to the resolving point in the spectrometer is affected without affecting the location of the point of velocity focus of the charged particle beam relative to the resolving point when the magnetic sector is rotated thereabout, said locus of centers defining a substantially straight line substantially in the plane of the charged particle beam path; 2. moving the magnetic sector translationally in a direction parallel to said straight line and substantially in the plane of the charged particle beam path to locate the point of charged particle beam velocity focus at the resolving point of the spectrometer; and thereafter 3. moving the magnetic sector rotationally about a center of rotation lying on said straight line and substantially in the plane of the charged particle beam path to simultaneously locate the point of charged particle beam angular focus at the resolving point of the spectrometer whereby the spectrometer is put into optimum focus.
Claim 3
Dependent Claim
43 words
moving the magnetic sector translationally in a direction parallel to said straight line and substantially in the plane of the charged particle beam path to locate the point of charged particle beam velocity focus at the resolving point of the spectrometer; and thereafter
Claim 4
Dependent Claim
43 words
moving the magnetic sector translationally in a direction parallel to said straight line and substantially in the plane of the charged particle beam path to locate the point of charged particle beam velocity focus at the resolving point of the spectrometer; and thereafter
Claim 5
Dependent Claim
28 words
A method according to claim 1 wherein the rotational motion of the magnetic sector is confined to a plane parallel to the plane of the charged particle beam.
Claim 6
Dependent Claim
38 words
A method according to claim 1 wherein the step of translationally moving the magnetic sector produces motion of said sector in a direction transverse to the direction of the charged particle beam upon entrance into the magnetic sector.
Claim 7
Dependent Claim
52 words
moving the magnetic sector rotationally about a center of rotation lying on said straight line and substantially in the plane of the charged particle beam path to simultaneously locate the point of charged particle beam angular focus at the resolving point of the spectrometer whereby the spectrometer is put into optimum focus.
Claim 8
Dependent Claim
52 words
moving the magnetic sector rotationally about a center of rotation lying on said straight line and substantially in the plane of the charged particle beam path to simultaneously locate the point of charged particle beam angular focus at the resolving point of the spectrometer whereby the spectrometer is put into optimum focus.
Claim 9
Dependent Claim
38 words
A method according to claim 1 wherein the step of translationally moving the magnetic sector produces motion of said sector in a direction parallel to the direction of the charged particle beam upon entrance into the magnetic sector.
Claim 10
Dependent Claim
38 words
A method according to claim 1 wherein the step of translationally moving the magnetic sector produces motion of said sector in a direction perpendicular to the direction of the charged particle beam upon entrance into the magnetic sector.
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) | 1975-06-20 | 1975-12-20 | 1976-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-20 | 1979-12-20 | 1980-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-20 | 1983-12-20 | 1984-06-20 | $7700.00 | Window Closed / Lapsed |