US3766381A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method of charge-particle spectroscopy for chemical analysis of a sample
Assignee: Kratos Analytical Ltd
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Filing: 1972-05-08
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Granted: 1973-10-16
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Expires: 1992-05-08
Abstract
Abstract An area of a sample is irradiated with electromagnetic radiation so as to release electrons from the area. The electrons are focused to form an image of the sample in an image plane. An apertured image plate is positioned in the image plane to permit only those electrons from a small region of the emitting area to pass. Electrons passing the aperture are energy analyzed. The result is the equivalent of using a microprobe to irradiate the small region. The particles may be retarded before they enter the analyzer, in order to increase sensitivity. A focusing system of five or more lens elements is shown for permitting the analyzer to be used with or without the lens plate without repositioning the system lenses.
Inventors
- 👤 J Watson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:31
CPC Classifications
H; H01; H01J; H01J49/00; H01J49/44; H01J49/46; H01J49/48; H01J49/484
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
154 words
Apparatus for charged-particle spectroscopy for chemical analysis of a sample comprising: a. an irradiation means for irradiating an extended area of a sample so as to release charged particles from the whole of that extended area; b. charged-particle focusing means for forming a chargedparticle image of said extended area of said sample in an image plane; c. screening means positioned in said image plane for obstructing the passage of a majority of said charged particles forming said image and having an aperture for passing only those charged particles emitted from a minor region of said area; d. an energy analyzer for analyzing the energies of the particles passing through said aperture in said screening means; and e. means for relatively moving said screening means and said sample in a direction generally parallel to said image plane to enable charged particles from different minor regions of said said area to pass to said energy analyzer.
Claim 2
Dependent Claim
154 words
Apparatus for charged-particle spectroscopy for chemical analysis of a sample comprising: a. an irradiation means for irradiating an extended area of a sample so as to release charged particles from the whole of that extended area; b. charged-particle focusing means for forming a chargedparticle image of said extended area of said sample in an image plane; c. screening means positioned in said image plane for obstructing the passage of a majority of said charged particles forming said image and having an aperture for passing only those charged particles emitted from a minor region of said area; d. an energy analyzer for analyzing the energies of the particles passing through said aperture in said screening means; and e. means for relatively moving said screening means and said sample in a direction generally parallel to said image plane to enable charged particles from different minor regions of said said area to pass to said energy analyzer.
Claim 3
Dependent Claim
34 words
Apparatus according to claim 1 wherein said focusing means comprises at least four mutually electrically insulated lens components through which the particles pass in turn, and means for applying respective potentials to said components.
Claim 4
Dependent Claim
26 words
Apparatus according to claim 1 wherein said energy analyzer comprises two concentrically mounted, mutually electrically insuLated metal hemispheres, and means for applying a voltage between them.
Claim 5
Dependent Claim
16 words
Apparatus according to claim 1 wherein said means for irradiating the sample comprises an X-ray source.
Claim 6
Dependent Claim
48 words
An apparatus as defined in claim 1 wherein said screening means comprises an apertured plate member which extends in said image plane, and said moving means includes drive means coupled to said apertured plate member for moving said plate member in a direction parallel to said image plane.
Claim 7
Dependent Claim
19 words
The apparatus of claim 5 wherein said focusing means comprises a lensing system having at least five lens components.
Claim 8
Independent Claim
133 words
A method of chamical analysis of a sample comprising: a. irradiating an extended area of the sample so as to release charged particles from the whole of that extended area; b. focusing said charged particles to form a charged particle image of said extended area of said sample in an image plane; c. inserting a screening means having an aperture into said image plane to obstruct the passage of all said charged particles forming said image except those emitted from a minor region of said area; d. analyzing the energies of the unobstructed particles in an energy analyzer; and e. relatively moving said screening means and said sample in a direction parallel to said image plane to enable charged particles from different minor regions of said area to pass to said energy analyzer.
Claim 9
Independent Claim
133 words
A method of chamical analysis of a sample comprising: a. irradiating an extended area of the sample so as to release charged particles from the whole of that extended area; b. focusing said charged particles to form a charged particle image of said extended area of said sample in an image plane; c. inserting a screening means having an aperture into said image plane to obstruct the passage of all said charged particles forming said image except those emitted from a minor region of said area; d. analyzing the energies of the unobstructed particles in an energy analyzer; and e. relatively moving said screening means and said sample in a direction parallel to said image plane to enable charged particles from different minor regions of said area to pass to said energy analyzer.
Claim 10
Dependent Claim
68 words
A method according to claim 7 wherein the step of analyzing the energies of the particles comprises deflecting the particles in an electrostatic field, positioning collector means to collect deflected particles whose energies lie within a limited range of values, and sweeping the strength of said electrostatic field through a range of values so as to sweep said collector means through the energy spectrum of the charged particles.
Claim 11
Dependent Claim
36 words
A method according to claim 7 including the further step of retarding the particles before they enter the analyzer whereby they enter the analyzer with lower energies than they had on being released from said sample.
Claim 12
Dependent Claim
59 words
A method according to claim 8 including the step of switching between a first mode of operation in which the particles are retarded, whereby they enter the analyzer with lower energies than they had on being released from said sample, and a second mode of operation, in which the particles are substantially not retarded before they enter the analyzer.
Claim 13
Dependent Claim
18 words
A method according to claim 10 wherein said step of switching is performed by altering electrical connections only.
References Cited (Backward Citations)
US2219405A
Cited
US3617741A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-15 | 1977-04-16 | 1977-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-15 | 1981-04-16 | 1981-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-15 | 1985-04-16 | 1985-10-16 | $7700.00 | Window Closed / Lapsed |