US3889113A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radioisotope-excited, energy-dispersive x-ray fluorescence apparatus
Assignee: COLUMBIA SCIENT IND Inc
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Filing: 1973-05-03
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Granted: 1975-06-10
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Expires: 1993-05-03
Abstract
Abstract Radioisotope-excited, energy-dispersive, X-ray fluorescence apparatus for positioning a plurality of disc sources in annular configuration in a helium-filled compartment and about the window of the vacuum cryostat housing the detector. The specimen holder leaves the specimen in air and the area and spacing of the specimen, detector and sources are such as to optimize operation about the plateau of the count rate distance curve and to produce an essentially flat detector response profile curve, with a welldefined cutoff.
Inventors
- 👤 John R Rhodes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:52
CPC Classifications
G; G01; G01N; G01N23/00; G01N23/22; G01N23/223; G01N2223/00; G01N2223/07; G01N2223/076
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
158 words
In a radioisotope X-ray fluorescence analyzer for analyzation of specimens in an atmospheric environment, said analyzer including a sealed radioisotope excitation source means, and a detection system for selecting the energies of the characteristic X-rays excited in a specimen under analysis and measuring their intensities, the improvement, comprising a first holder for the source means, said holder defining a plurality of receptacles disposed in annular array, said source means being a plurality of radioactive sources being disposed one within each of said receptacles, a second holder for a detector in the detection system, said first and second holders being located on the same side of the specimen, said first holder being encased in a helium-filled compartment having a window toward the specimen, the source being located at a distance in the range of 0.05 to 0.4 inch of said window and the specimen being positionable in the atmospheric environment on the side of said window opposite said source.
Claim 2
Dependent Claim
158 words
In a radioisotope X-ray fluorescence analyzer for analyzation of specimens in an atmospheric environment, said analyzer including a sealed radioisotope excitation source means, and a detection system for selecting the energies of the characteristic X-rays excited in a specimen under analysis and measuring their intensities, the improvement, comprising a first holder for the source means, said holder defining a plurality of receptacles disposed in annular array, said source means being a plurality of radioactive sources being disposed one within each of said receptacles, a second holder for a detector in the detection system, said first and second holders being located on the same side of the specimen, said first holder being encased in a helium-filled compartment having a window toward the specimen, the source being located at a distance in the range of 0.05 to 0.4 inch of said window and the specimen being positionable in the atmospheric environment on the side of said window opposite said source.
Claim 3
Dependent Claim
25 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 1, wherein said window between the source and specimen is a membrane composed of Mylar.
Claim 4
Dependent Claim
24 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 1, wherein the pressure in said helium-filled compartment is substantially equal to atmospheric pressure.
Claim 5
Dependent Claim
31 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 1, wherein the apace between the specimen and the window located between the source and specimen is less than 0.05 inches.
Claim 6
Dependent Claim
56 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 1, wherein said receptacles of said first holder comprise a plurality of bores for receiving substantially identically shaped disc sources about an annular aperture, and said radioactive elements defining said source comprise an array of substantiAlly identically shaped disc sources retained within said plurality of bores.
Claim 7
Dependent Claim
34 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 5, wherein said plurality of substantially identically shaped disc sources includes discs of a first radioactive material and discs of a second radioactive material.
Claim 8
Dependent Claim
32 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 5, wherein said plurality of bores are each inclined toward the axis of said annular aperture by not more than 20* .
Claim 9
Dependent Claim
17 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 5, wherein said first holder is replaceable.
Claim 10
Dependent Claim
148 words
In a radioisotope X-ray fluorescence analyzer for analyzing specimens in an atmospheric environment, said analyzer including a sealed radioisotope excitation source means of annular geometry, and a detection system for selecting the energies of the characteristic X-rays excited in a specimen under analysis and measuring their intensities, the improvement, comprising a first holder for the source located at a diatance from said specimen in the range of 0.05 to 0.20 inch, within which range a detector response profile is produced having an approximately flat response within 10 percent of maximum, said holder defining a plurality of receptacles and a central aperture about which said receptacles are defined, said source means being a plurality of radioactive elements received one within each of said receptacles, and a second holder for a detector in the detection system, said first and second holders being located on the same side of the specimen.
Claim 11
Dependent Claim
148 words
In a radioisotope X-ray fluorescence analyzer for analyzing specimens in an atmospheric environment, said analyzer including a sealed radioisotope excitation source means of annular geometry, and a detection system for selecting the energies of the characteristic X-rays excited in a specimen under analysis and measuring their intensities, the improvement, comprising a first holder for the source located at a diatance from said specimen in the range of 0.05 to 0.20 inch, within which range a detector response profile is produced having an approximately flat response within 10 percent of maximum, said holder defining a plurality of receptacles and a central aperture about which said receptacles are defined, said source means being a plurality of radioactive elements received one within each of said receptacles, and a second holder for a detector in the detection system, said first and second holders being located on the same side of the specimen.
Claim 12
Dependent Claim
52 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 9, wherein said receptacles within said first holder comprise a plurality of bores for receiving substantially identically shaped disc sources about said central aperture, and said source is an array of substantially identically shaped disc sources received within said plurality of bores.
Claim 13
Dependent Claim
20 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 9, including a shield between said first and second holders.
Claim 14
Dependent Claim
34 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 9, wherein the distance from said source to said specimen assures a fall-off to 50 percent of maximum value within a 0.02 inch radius.
Claim 15
Dependent Claim
93 words
In a radioisotope X-ray fluorescence analyzer including a sealed radioisotope excitation source means of annular geometry, and a detection system for selecting the energies of the characteristic X-rays excited in a specimen under analysis and measuring their intensities, the improvement, comprising a first holder for the source, a second holder for a detector in the detection system, said first and second holders being located on the same side of the specimen, said second holder located at a distance from said specimen to provide operation near the plateau of the count rate distance curve.
Claim 16
Dependent Claim
93 words
In a radioisotope X-ray fluorescence analyzer including a sealed radioisotope excitation source means of annular geometry, and a detection system for selecting the energies of the characteristic X-rays excited in a specimen under analysis and measuring their intensities, the improvement, comprising a first holder for the source, a second holder for a detector in the detection system, said first and second holders being located on the same side of the specimen, said second holder located at a distance from said specimen to provide operation near the plateau of the count rate distance curve.
Claim 17
Dependent Claim
38 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 13, wherein said count rate distance plateau decreases less than about 1/2 percent for a change in relative position of said specimen and said detector of 0.02 inches.
Claim 18
Dependent Claim
125 words
In a radioisotope X-ray fluorescence analyzer including a sealed radioisotope excitation source of annular geometry, and a detection system for selecting the energies of the characteristic X-rays excited in a specimen under analysis and measuring their intensities, the improvement, comprising a first holder for the source located at a distance in the range of 0.1 inches to 0.14 inches from said specimen for producing a detector response profile having an approximately flat response within 10 percent of maximum, and a second holder for a detector in the detection system, said first and second holders being located on the said side of the specimen, said second holder located at a distance from said specimen to proviDe operation near the plateau of the count rate distance curve.
Claim 19
Dependent Claim
125 words
In a radioisotope X-ray fluorescence analyzer including a sealed radioisotope excitation source of annular geometry, and a detection system for selecting the energies of the characteristic X-rays excited in a specimen under analysis and measuring their intensities, the improvement, comprising a first holder for the source located at a distance in the range of 0.1 inches to 0.14 inches from said specimen for producing a detector response profile having an approximately flat response within 10 percent of maximum, and a second holder for a detector in the detection system, said first and second holders being located on the said side of the specimen, said second holder located at a distance from said specimen to proviDe operation near the plateau of the count rate distance curve.
Claim 20
Dependent Claim
61 words
A radioisotope X-ray fluorescence analyzer as set forth in claim 15, wherein the distance from said source to said specimen assures a fall-off to 50 percent of maximum value with a 0.02 inch radius, and said count rate distance plateau decreases less than about 1/2 percent for a change in relative position of said specimen and said detector of 0.02 inches.
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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) | 1978-06-09 | 1978-12-09 | 1979-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-09 | 1982-12-09 | 1983-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-09 | 1986-12-09 | 1987-06-10 | $7700.00 | Window Closed / Lapsed |