Patent US7279120B2 successfully refreshed from Google Patents.
US7279120B2
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Doped cadmium tungstate scintillator with improved radiation hardness
Assignee: Intematix Corp
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Filing: 2004-08-27
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Granted: 2007-10-09
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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 21:33
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.
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