US3868512A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite input screen for X-ray imaging devices
Assignee: General Electric Co
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Filing: 1973-09-04
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Granted: 1975-02-25
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Expires: 1993-09-04
Abstract
Abstract A composite screen is made from a mixture of CsI:Tl and Gd2O2S: Tb phosphors. The composite is formed by slowly removing a mixture of the phosphors from a hot zone so that molten CsI:Tl progressively cools and hardens to bind the Gd2O2S:Tl particles together. When completed, the composite material is sliced to form a plurality of screens.
Inventors
- 👤 Jerome S Prener
- 👤 Stanley J Lubowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:03
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/36; H01J29/38; H01J29/385; H01J9/00; H01J9/20
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
24 words
AN IMPROVED SCREEN FOR X-RAY IMAGING DEVICES COMPRISING: A WAFER COMPRISING A HIGH DENSITY, HIGH CONVERSION EFFICIENCY PHOSPHOR POWDER BONDED TOGETHER WITH DOPED CLS;
Claim 2
Dependent Claim
24 words
AN IMPROVED SCREEN FOR X-RAY IMAGING DEVICES COMPRISING: A WAFER COMPRISING A HIGH DENSITY, HIGH CONVERSION EFFICIENCY PHOSPHOR POWDER BONDED TOGETHER WITH DOPED CLS;
Claim 3
Dependent Claim
15 words
An improved screen as set forth in claim 1 wherein said doped CsI comprised CsI:Tl.
Claim 4
Dependent Claim
19 words
An improved screen as set forth in claim 1 wherein said high density, high conversion efficiency phosphor comprises Gd2S2O:Tb.
Claim 5
Dependent Claim
19 words
An improved screen as set forth in claim 1 wherein said screen is from 3 to 10 mils thick.
Claim 6
Independent Claim
89 words
The method of makinG an improved input screen for x-ray imaging devices comprising the steps of: mixing together in a container Gd2O2S:Tb and doped CsI in the ratio of about 1:2.5 by weight; sealing said container under vacuum; heating said container to at least 621* C to melt said doped CsI; slowing withdrawing said container from the heat to form a composite of Gd2O2S:Tb - CsI; removing the composite from said container; and forming a plurality of wafers from said composite, wherein each wafer comprises a complete input screen.
Claim 7
Independent Claim
89 words
The method of makinG an improved input screen for x-ray imaging devices comprising the steps of: mixing together in a container Gd2O2S:Tb and doped CsI in the ratio of about 1:2.5 by weight; sealing said container under vacuum; heating said container to at least 621* C to melt said doped CsI; slowing withdrawing said container from the heat to form a composite of Gd2O2S:Tb - CsI; removing the composite from said container; and forming a plurality of wafers from said composite, wherein each wafer comprises a complete input screen.
Claim 8
Dependent Claim
17 words
The method as set forth in claim 5 wherein said container is heated to approximately 700* C.
Claim 9
Dependent Claim
24 words
The method as set forth in claim 5 wherein said composite is formed by withdrawing the container at 0.1 to 1.0 centimeters per hour.
Claim 10
Dependent Claim
36 words
The method as set forth in claim 5 wherein said wafers are formed by slicing said crystal and grinding the slices to a curved surface configuration to form an input screen for an x-ray imaging device.
Claim 11
Dependent Claim
14 words
The method as set forth in claim 5 wherein said doped CdI comprises CsI:Tl.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-24 | 1978-08-26 | 1979-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-24 | 1982-08-26 | 1983-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-24 | 1986-08-26 | 1987-02-25 | $7700.00 | Window Closed / Lapsed |