Patent US5874738A successfully refreshed from Google Patents.
US5874738A
Expired / Lapsed
US
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Scintillation crystal modules and methods of making the same
Assignee: Saint Gobain Ceramics and Plastics Inc
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Filing: 1997-06-20
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Granted: 1999-02-23
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Expires: 2017-06-20
Abstract
Abstract A scintillation crystal module having an epoxy seal which has a coefficient of thermal expansion which is substantially the same as the backcap of the gamma camera. Among the suitable epoxy systems, the CTE of the epoxy could be modified somewhat by choosing a different catalyst or by adjusting the resin:catalyst ratio. The presently preferred epoxy system is a STYCAST® 2850 FT system available from W. R. Grace & Co. Using "catalyst 9" or "catalyst 11" from that system, a CTE of approximately 17.33×10 -6 to approximately 19.4×10 -6 in/in° F. can be easily achieved. It has been discovered through analysis using FEA that an epoxy with a CTE in the range of 9.0 to 20.0×10 -6 in/in° F. provides satisfactory results in preventing seal separation during ±40° F. temperature cycles. A method of making a scintillation crystal module includes the preparation of an epoxy seal having a coefficient of thermal expansion which is substantially the same as the backcap of the module, and assembling the seal, backcap, glass, and crystal in a conventional manner.
Inventors
- 👤 Scott T. Huth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:27
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/16; G01T1/20; G01T1/2002
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
79 words
A scintillation crystal module comprising: a) a metal backcap having a first coefficient of thermal expansion; b) an optically transparent window; c) a scintillation crystal located between said optically transparent window and said metal backcap; and d) an epoxy seal located between said optically transparent window and said metal backcap, said epoxy seal hermetically sealing said module, wherein said epoxy seal has a second coefficient of thermal expansion which is closely matched to said first coefficient of thermal expansion.
Claim 2
Dependent Claim
79 words
A scintillation crystal module comprising: a) a metal backcap having a first coefficient of thermal expansion; b) an optically transparent window; c) a scintillation crystal located between said optically transparent window and said metal backcap; and d) an epoxy seal located between said optically transparent window and said metal backcap, said epoxy seal hermetically sealing said module, wherein said epoxy seal has a second coefficient of thermal expansion which is closely matched to said first coefficient of thermal expansion.
Claim 3
Dependent Claim
14 words
A scintillation crystal module according to claim 1, wherein: said metal backcap is aluminum.
Claim 4
Dependent Claim
16 words
A scintillation crystal module according to claim 2, wherein: said optically transparent window is K+ glass.
Claim 5
Dependent Claim
40 words
A scintillation crystal module according to claim 2, wherein: said first coefficient of thermal expansion is approximately 13.3×10 -6 in/in° F., and said second coefficient of thermal expansion is between approximately 9×10 -6 in/in° F. and 20×10 -6 in/in° F.
Claim 6
Dependent Claim
23 words
A scintillation crystal module according to claim 1, further comprising: e) an array of photo detectors optically coupled to said optically transparent window.
Claim 7
Dependent Claim
26 words
A scintillation crystal module according to claim 1, wherein: said epoxy seal has a modulus of elasticity of between approximately 1×10 5 and 5×10 5 .
Claim 8
Independent Claim
71 words
A method of making a scintillation crystal module, comprising: a) bonding a scintillation crystal to an optically transparent window; b) obtaining a metal backcap having a first coefficient of thermal expansion; c) obtaining an epoxy with a second coefficient of thermal expansion, said second coefficient of thermal expansion being approximately equal to said first coefficient of thermal expansion; and d) bonding the transparent window to the metal backcap with the epoxy.
Claim 9
Independent Claim
71 words
A method of making a scintillation crystal module, comprising: a) bonding a scintillation crystal to an optically transparent window; b) obtaining a metal backcap having a first coefficient of thermal expansion; c) obtaining an epoxy with a second coefficient of thermal expansion, said second coefficient of thermal expansion being approximately equal to said first coefficient of thermal expansion; and d) bonding the transparent window to the metal backcap with the epoxy.
Claim 10
Dependent Claim
22 words
A method according to claim 7, wherein: said obtaining an epoxy comprises obtaining a resin and a catalyst and preparing the epoxy.
Claim 11
Dependent Claim
16 words
A method according to claim 8, wherein: said bonding the transparent window comprises curing the epoxy.
Claim 12
Dependent Claim
25 words
A method according to claim 7, further comprising: e) obtaining an array of photo detectors; and f) optically coupling the array to the transparent window.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 2002-02-22 | 2002-08-24 | 2003-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-02-22 | 2006-08-24 | 2007-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-02-22 | 2010-08-24 | 2011-02-23 | $7700.00 | Window Closed / Lapsed |