US7279120B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Doped cadmium tungstate scintillator with improved radiation hardness
Assignee: Intematix Corp
•
Filing: 2004-08-27
•
Granted: 2007-10-09
•
Expires: 2024-08-27
Abstract
Abstract This invention provides novel cadmium tungstate scintillator materials that show improved radiation hardness. In particular, it was discovered that doping of cadmium tungstate (CdWO 4 ) with trivalent metal ions or monovalent metal ions is particularly effective in improving radiation hardness of the scintillator material.
Inventors
- 👤 Shifan Cheng
- 👤 Yi-Qun Li
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:17
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/67; C09K11/68; C09K11/681; C09K11/682; C04; C04B; C04B35/00; C04B35/01; C04B35/495; C09K11/74; C09K11/7457; C09K11/77; C09K11/7708; C30; C30B; C30B15/00; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/32; G; G21; G21K; G21K4/00; C04B2235/00; C04B2235/02; C04B2235/30; C04B2235/32; C04B2235/3201; C04B2235/3203; C04B2235/3224; C04B2235/3225; C04B2235/3227; C04B2235/3229; C04B2235/3231; C04B2235/3258; C04B2235/3284; C04B2235/3289; C04B2235/3291; C04B2235/3298
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
45 words
A sintered body comprising a scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, the scintillator composition being a component of the sintered body, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 .
Claim 2
Dependent Claim
45 words
A sintered body comprising a scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, the scintillator composition being a component of the sintered body, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 .
Claim 3
Dependent Claim
104 words
The sintered body of claim 1 , wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; B is a trivalent metal ion selected from the group consisting of Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; X ranges from 0 to about 0.01; Y ranges from 0 to about 0.01; and at least one of X or Y is non-zero.
Claim 4
Dependent Claim
118 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; B is a trivalent metal ion selected from the group consisting of: Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; wherein X is about 0.005; and, Y ranges from 0 to about 0.01.
Claim 5
Dependent Claim
118 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; B is a trivalent metal ion selected from the group consisting of: Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; wherein X is about 0.005; and, Y ranges from 0 to about 0.01.
Claim 6
Dependent Claim
118 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof: B is a trivalent metal ion selected from the group consisting of: Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; wherein X is about 0.001; and Y ranges from 0 to about 0.01.
Claim 7
Dependent Claim
118 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof: B is a trivalent metal ion selected from the group consisting of: Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; wherein X is about 0.001; and Y ranges from 0 to about 0.01.
Claim 8
Dependent Claim
118 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; B is a trivalent metal ion selected from the group consisting of: Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; wherein X is about 0.001 or about 0.005; and, wherein Y is 0.
Claim 9
Dependent Claim
118 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; B is a trivalent metal ion selected from the group consisting of: Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; wherein X is about 0.001 or about 0.005; and, wherein Y is 0.
Claim 10
Dependent Claim
12 words
The sintered body of claim 2 , wherein Y is about 0.005.
Claim 11
Dependent Claim
12 words
The sintered body of claim 2 , wherein Y is about 0.001.
Claim 12
Dependent Claim
11 words
The sintered body of claim 6 , wherein X is 0.
Claim 13
Dependent Claim
11 words
The sintered body of claim 7 , wherein X is 0.
Claim 14
Dependent Claim
17 words
The sintered body of claim 2 , wherein X is zero, and Y is greater than zero.
Claim 15
Dependent Claim
13 words
The sintered body of claim 10 , wherein B is Gd 3+ .
Claim 16
Dependent Claim
95 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; wherein X ranges from 0 to about 0.01; and, B is Gd 3+ and Y ranges from about 0.0002 to about 0.001.
Claim 17
Dependent Claim
95 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; wherein X ranges from 0 to about 0.01; and, B is Gd 3+ and Y ranges from about 0.0002 to about 0.001.
Claim 18
Dependent Claim
124 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; B is a trivalent metal ion selected from the group consisting of: Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; wherein X and Y are both 0.01 or less; and, wherein X and Y are both greater than zero.
Claim 19
Dependent Claim
124 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; B is a trivalent metal ion selected from the group consisting of: Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; wherein X and Y are both 0.01 or less; and, wherein X and Y are both greater than zero.
Claim 20
Dependent Claim
21 words
The scintillator composition of claim 13 , wherein A is K 1+ or Rb 1+ and B is Bi 3+ .
Claim 21
Dependent Claim
119 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; B is a trivalent metal ion selected from the group consisting of: Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; wherein X ranges from greater than zero to about 0.01, and Y is zero.
Claim 22
Dependent Claim
119 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Li, Na, K, Rb, Cs, Ag, Tl, and combinations thereof; B is a trivalent metal ion selected from the group consisting of: Bi, Y, La, Ce, Pr, Nd, Gd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof; wherein X ranges from greater than zero to about 0.01, and Y is zero.
Claim 23
Dependent Claim
119 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Na, K and combinations thereof; B is a trivalent metal ion selected from the group consisting of: Bi, Gd, and combinations thereof; wherein said doped cadmium tungstate is selected from the group consisting of Cd 0.9995 Na 0.0005 WO 4 , Cd 0.9995 Gd 0.0005 WO 4 , and Cd 0.999 (KBi) 0.001 WO 4 .
Claim 24
Dependent Claim
119 words
A scintillator composition comprising a cadmium tungstate doped with a monovalent metal ion and/or a trivalent metal ion, wherein said scintillator composition shows higher radiation tolerance than undoped CdWO 4 ; and, wherein the doped cadmium tungstate is represented by the formula: Cd (1−(x+y)) A x B y WO 4 where: A is a monovalent metal ion selected from the group consisting of: Na, K and combinations thereof; B is a trivalent metal ion selected from the group consisting of: Bi, Gd, and combinations thereof; wherein said doped cadmium tungstate is selected from the group consisting of Cd 0.9995 Na 0.0005 WO 4 , Cd 0.9995 Gd 0.0005 WO 4 , and Cd 0.999 (KBi) 0.001 WO 4 .
Claim 25
Dependent Claim
21 words
A detector element of an X-ray CT scanner comprising a scintillator composition of any one of claims 1 through 16 .
Claim 26
Dependent Claim
28 words
An x-ray detector comprising: a scintillator composition of any one of claims 1 through 16 ; and a photodetector disposed to detect light emitted by said scintillator composition.
Claim 27
Dependent Claim
22 words
The detector of claim 18 , wherein said photodetector is selected from the group consisting of a photomultiplier, a photodiode, and photographic-film.
Claim 28
Independent Claim
42 words
A method of producing an X-ray image, said method comprising: providing an x-ray detector comprising a scintillator composition of any one of claims 1 through 16 ; subjecting said scintillator composition to X-ray radiation; and detecting light emission from said scintillator composition.
References Cited (Backward Citations)
US2361467A
Cited
US3668143A
Cited
US4115312A
Cited
US4230510A
Cited
US4242221A
Cited
US4362946A
Cited
US4466929A
Cited
US4466930A
Cited
US4421671A
Cited
US4473513A
Cited
US4518546A
Cited
US4518545A
Cited
US4571312A
Cited
US4747973A
Cited
US4799094A
Cited
US4883956A
Cited
US4933562A
Cited
US5166073A
Cited
US6717174B2
Cited
US5360557A
Cited
US5318722A
Cited
US5391876A
Cited
US5057692A
Cited
US5484750A
Cited
US5245648A
Cited
US5306907A
Cited
US5510644A
Cited
US5434418A
Cited
US5640017A
Cited
US6194726B1
Cited
US5587611A
Cited
EP0795631A1
Cited
US5838759A
Cited
US5650626A
Cited
US5753921A
Cited
US5864146A
Cited
US5834782A
Cited
US6093347A
Cited
US5912942A
Cited
US5898753A
Cited
US6087618A
Cited
US6563121B1
Cited
US6358441B2
Cited
US6504156B1
Cited
US6774556B2
Cited
US6553092B1
Cited
US6496250B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2010-10-08 | 2011-04-09 | 2011-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2014-10-08 | 2015-04-09 | 2015-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2018-10-08 | 2019-04-09 | 2019-10-09 | $7700.00 | Window Closed / Lapsed |