US5882547A
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US
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X-ray scintillators and devices incorporating them
Assignee: General Electric Co
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Filing: 1997-05-19
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Granted: 1999-03-16
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Expires: 2017-05-19
Abstract
Abstract Decay time in scintillator compositions comprising yttrium or lutetium and gadolinium oxides and europium oxide is decreased by incorporating therein at least one of the oxides of ytterbium, samarium, praseodymium, neodymium, dysprosium, holmium, thulium, cerium and erbium as an acceptor. Other properties including afterglow and radiation damage are maintained at acceptable levels.
Inventors
- 👤 Michael John Lynch
- 👤 Steven Jude Duclos
- 👤 Charles David Greskovich
- 👤 Alok Mani Srivastava
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:15
CPC Classifications
G; G21; G21K; G21K4/00; C; C04; C04B; C04B35/00; C04B35/50; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7766; C09K11/7767; C09K11/7783; C09K11/7784; G01; G01T; G01T1/00; G01T1/16; G01T1/20; G01T1/202; G01T1/2023
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
80 words
A scintillator composition comprising the following and any reaction products thereof: a major proportion of yttrium oxide or lutetium oxide and a minor proportion of gadolinium oxide as matrix materials, europium oxide in the amount of about 1-30 mole percent based on total scintillator composition as an activator producing at least 99% of total emission, and a minor decay time-decreasing proportion of at least one of the oxides of neodymium, dysprosium, samarium, holmium, erbium, thulium and cerium as an acceptor.
Claim 2
Dependent Claim
80 words
A scintillator composition comprising the following and any reaction products thereof: a major proportion of yttrium oxide or lutetium oxide and a minor proportion of gadolinium oxide as matrix materials, europium oxide in the amount of about 1-30 mole percent based on total scintillator composition as an activator producing at least 99% of total emission, and a minor decay time-decreasing proportion of at least one of the oxides of neodymium, dysprosium, samarium, holmium, erbium, thulium and cerium as an acceptor.
Claim 3
Dependent Claim
31 words
A composition according to claim 1 comprising yttrium oxide, gadolinium oxide in an amount up to about 45 mole percent and europium oxide in the amount of about 6.1-12 mole percent.
Claim 4
Dependent Claim
20 words
A composition according to claim 2 wherein the acceptor is holmium oxide in the amount of about 0.01-2.0 mole percent.
Claim 5
Dependent Claim
20 words
A composition according to claim 2 wherein the acceptor is erbium oxide in the amount of about 0.01-2.0 mole percent.
Claim 6
Dependent Claim
20 words
A composition according to claim 2 wherein the acceptor is thulium oxide in the amount of about 0.01-2.0 mole percent.
Claim 7
Dependent Claim
20 words
A composition according to claim 2 wherein the acceptor is cerium oxide in the amount of about 60-10,000 mole ppm.
Claim 8
Dependent Claim
20 words
A composition according to claim 2 wherein the acceptor is samarium oxide in the amount of about 0.01-2.0 mole percent.
Claim 9
Dependent Claim
20 words
A composition according to claim 2 wherein the acceptor is neodymium oxide in the amount of about 0.02-0.5 mole percent.
Claim 10
Dependent Claim
20 words
A composition according to claim 2 wherein the acceptor is dysprosium oxide in the amount of about 0.01-2.0 mole percent.
Claim 11
Dependent Claim
31 words
A composition according to claim 9 comprising yttrium oxide, gadolinium oxide in an amount up to about 45 mole percent and europium oxide in the amount of about 3-7.5 mole percent.
Claim 12
Independent Claim
114 words
A method for producing an X-ray image which comprises: preparing a scintillator composition comprising the following and any reaction products thereof: a major proportion of yttrium oxide or lutetium oxide and a minor proportion of gadolinium oxide as matrix materials, europium oxide in the amount of about 1-30 mole percent based on total scintillator composition as an activator producing at least 99% of total emission, and a minor decay time-decreasing proportion of at least one of the oxides of neodymium, dysprosium, samarium, holmium, erbium, thulium and cerium as an acceptor; incorporating a scintillator of said composition in an X-ray detector, subjecting said scintillator composition to X-ray radiation and measuring visible emission from said europium.
Claim 13
Independent Claim
114 words
A method for producing an X-ray image which comprises: preparing a scintillator composition comprising the following and any reaction products thereof: a major proportion of yttrium oxide or lutetium oxide and a minor proportion of gadolinium oxide as matrix materials, europium oxide in the amount of about 1-30 mole percent based on total scintillator composition as an activator producing at least 99% of total emission, and a minor decay time-decreasing proportion of at least one of the oxides of neodymium, dysprosium, samarium, holmium, erbium, thulium and cerium as an acceptor; incorporating a scintillator of said composition in an X-ray detector, subjecting said scintillator composition to X-ray radiation and measuring visible emission from said europium.
Claim 14
Dependent Claim
35 words
A method according to claim 11 wherein said scintillator composition comprises yttrium oxide, gadolinium oxide in an amount up to about 45 mole percent and europium oxide in the amount of about 6.1-12 mole percent.
Claim 15
Dependent Claim
35 words
A method according to claim 11 wherein said scintillator composition comprises yttrium oxide, gadolinium oxide in an amount up to about 45 mole percent and europium oxide in the amount of about 3-7.5 mole percent.
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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) | 2002-03-15 | 2002-09-14 | 2003-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-03-15 | 2006-09-14 | 2007-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-03-15 | 2010-09-14 | 2011-03-16 | $7700.00 | Window Closed / Lapsed |