US4656359A
Expired / Lapsed
US
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Scintillation crystal for a radiation detector
Assignee: Siemens Medical Solutions USA Inc
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Filing: 1986-03-10
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Granted: 1987-04-07
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Expires: 2006-03-10
Abstract
Abstract A scintillation crystal is provided for a radiation detector, which comprises a first layer of a crystal material having relatively poor mechanical properties, however having a high energy resolution; and a second layer of a crystal material having relatively good mechanical and optical properties. Both layers are arranged in sandwich form.
Inventors
- 👤 Dennis E. Persyk
- 👤 Everett W. Stoub
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:54
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/16; G01T1/20; G01T1/202; G01T1/2002
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
71 words
A scintillation crystal for a radiation detector, comprising: (a) a first layer of a crystal material which has a high energy resolution; and (b) a second layer of a different crystal material, said second layer being located on top of said first layer and being thin with respect thereto, the second layer protecting the first layer against breakage and making a negligable contribution to the scintillation properties of the first layer.
Claim 2
Dependent Claim
71 words
A scintillation crystal for a radiation detector, comprising: (a) a first layer of a crystal material which has a high energy resolution; and (b) a second layer of a different crystal material, said second layer being located on top of said first layer and being thin with respect thereto, the second layer protecting the first layer against breakage and making a negligable contribution to the scintillation properties of the first layer.
Claim 3
Dependent Claim
18 words
A scintillation crystal according to claim 1, wherein said first layer is made of thallium-activated sodium iodide (NaI[Tl]).
Claim 4
Dependent Claim
35 words
A scintillation crystal according to claim 1, wherein said second layer is made of a crystal material selected from the group consisting of cesium iodide (CsI), sodium-activated cesium iodide (CsI[Na]) and thallium-activated cesium iodide (CsI[Tl]).
Claim 5
Dependent Claim
23 words
A scintillation crystal according to claim 1, wherein the first layer has a thickness in the range of 1/4 inch to 1 inch.
Claim 6
Dependent Claim
23 words
A scintillation crystal according to claim 1, wherein the second layer has a thickness in the range of 0.1 mm to 1 mm.
Claim 7
Dependent Claim
26 words
The scintillation crystal of claim 1, further comprising a third layer of a crystal material, said first layer being sandwiched between said second and third layers.
Claim 8
Dependent Claim
35 words
A scintillation crystal according to claim 6, wherein said third layer is made of a crystal material selected from the group consisting of cesium iodide (CsI), sodium-activated cesium iodide (CsI[Na]) and thallium-activated cesium iodide (CsI[Tl]).
Claim 9
Dependent Claim
48 words
A scintillation crystal according to claim 6, wherein said first layer is made of thallium-activated sodium iodide (NaI[Tl]) and said second and third layers are made of a crystal material selected from the group consisting of cesium iodide (CsI), sodium-activated cesium iodide (CsI[Na]) and thallium-activated cesium iodide (CsI[Te]).
Claim 10
Dependent Claim
23 words
A scintillation crystal according to claim 6, wherein the third layer has a thickness in the range of 0.1 mm to 1 mm.
Claim 11
Independent Claim
83 words
A method for making a scintillation crystal, comprising the following steps: (a) placing a substrate having a surface in an evaporation container; (b) evaporating within said container a first crystal material such that it deposits upon said surface to form a second crystal layer; and (c) evaporating within said container a second crystal material such that it deposits upon the second crystal layer as a first crystal layer to form a two-layer crystal sandwich, the second crystal material having a high energy resolution.
Claim 12
Independent Claim
83 words
A method for making a scintillation crystal, comprising the following steps: (a) placing a substrate having a surface in an evaporation container; (b) evaporating within said container a first crystal material such that it deposits upon said surface to form a second crystal layer; and (c) evaporating within said container a second crystal material such that it deposits upon the second crystal layer as a first crystal layer to form a two-layer crystal sandwich, the second crystal material having a high energy resolution.
Claim 13
Dependent Claim
20 words
A method according to claim 10, further comprising the step of sealing the two-layer crystal sandwich with a metal cover.
Claim 14
Dependent Claim
30 words
A method according to claim 10, wherein said first crystal material is selected from the group consisting of cesium iodide (CsI), sodium-activated cesium iodide (CsI[Na]) and thallium-activated cesium iodide (CsI[Tl]).
Claim 15
Dependent Claim
16 words
A method according to claim 10, wherein said second crystal material is thallium-activated sodium iodide (NaI[Tl]).
Claim 16
Dependent Claim
16 words
A method according to claim 10, further comprising the step of annealing the two-layer crystal sandwich.
Claim 17
Dependent Claim
38 words
The method of claim 10, further comprising the step of evaporating within said container a third crystal material such that it deposits upon the first crystal layer as a third crystal layer to form a three-layer crystal sandwich.
Claim 18
Dependent Claim
20 words
A method according to claim 15, further comprising the step of sealing the three-layer crystal sandwich with a metal cover.
Claim 19
Dependent Claim
30 words
A method according to claim 15, wherein said third crystal material is selected from the group consisting of cesium iodide (CsI), sodium-activated cesium iodide (CsI[Na]) and thallium-activated cesium iodide (CsI[Tl]).
Claim 20
Dependent Claim
43 words
A method according to claim 15, wherein said second crystal material is thallium-activated sodium iodide (NaI[Tl]) and wherein the first and third crystal material are selected from the group consisting of cesium iodide (CsI), sodium-activated cesium iodide (CsI[Na]) and thallium-activated cesium iodide (CsI[Tl]).
Claim 21
Dependent Claim
20 words
A method according to claim 18, further comprising the steps of sealing the three-layer crystal sandwich with an aluminum cover.
Claim 22
Dependent Claim
16 words
A method according to claim 15, further comprising the step of annealing the three-layer crystal sandwich.
Claim 23
Dependent Claim
70 words
A radiation detector, comprising a scintillation crystal which comprises: (a) a first layer of a crystal material having a high energy resolution; and (b) a second layer of a crystal material, said second layer being located on top of said first layer and being thin with respect thereto, the second layer protecting the first layer against breakage and making a negligable contribution to the scintillation properties of the first layer.
Claim 24
Dependent Claim
70 words
A radiation detector, comprising a scintillation crystal which comprises: (a) a first layer of a crystal material having a high energy resolution; and (b) a second layer of a crystal material, said second layer being located on top of said first layer and being thin with respect thereto, the second layer protecting the first layer against breakage and making a negligable contribution to the scintillation properties of the first layer.
Claim 25
Dependent Claim
17 words
The radiation detector of claim 21, further comprising a gamma-radiation scintillation camera head containing said scintillation crystal.
Claim 26
Dependent Claim
59 words
A scintillation crystal, comprising: a first layer of thallium-activated sodium iodide (NaI[Tl]); and a second layer selected from the group consisting of cesium iodide (CsI), sodium-activated cesium iodide (CsI[Na]) and thallium-activated cesium iodide (CsI[Tl]), said second layer being thin with respect to said first layer and protecting it against breakage and making a negligible contribution to its scintillation properties.
Claim 27
Dependent Claim
59 words
A scintillation crystal, comprising: a first layer of thallium-activated sodium iodide (NaI[Tl]); and a second layer selected from the group consisting of cesium iodide (CsI), sodium-activated cesium iodide (CsI[Na]) and thallium-activated cesium iodide (CsI[Tl]), said second layer being thin with respect to said first layer and protecting it against breakage and making a negligible contribution to its scintillation properties.
Claim 28
Dependent Claim
40 words
The scintillation crystal of claim 23, further comprising a third layer selected from the group consisting of cesium iodide (CsI), sodium-activated cesium iodide (CsI[Na]) and thallium-activated cesium iodide (CsI[Tl]), said first layer being sandwiched between said second and third layers.
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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) | 1990-04-06 | 1990-10-06 | 1991-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-06 | 1994-10-06 | 1995-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-06 | 1998-10-06 | 1999-04-07 | $7700.00 | Window Closed / Lapsed |