Patent US3103356A successfully refreshed from Google Patents.
USRE28751E
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US
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X- and gamma-ray sensitive image intensification tube
Assignee: Varian Medical Systems Inc
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Filing: 1973-10-17
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Granted: 1976-03-30
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Expires: 1993-10-17
Abstract
Abstract The invention relates to an X- and Gamma-ray sensitive image intensification tube for use in a so-called gamma camera or the like, which tube preferably has a single crystal input phosphor.
Inventors
- 👤 Jack Ball
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:30
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/61; C09K11/615; C09K11/616; G; G01; G01T; G01T1/00; G01T1/16; G01T1/161; G01T1/164; G01T1/1641; G01T1/1645; G21; G21K; G21K4/00; H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/36; H01J29/38; H01J29/385; H01J31/00; H01J31/08; H01J31/50; H01J31/501
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
140 words
In an image-forming device including an image intensification tube, .Iadd.said tube including an evacuated envelope, .Iaddend.and .Iadd.said device further including .Iaddend.means to reproduce an image output from said tube, an improved image tube input phosphor layer comprising: a. a single crystalline sheet .Iadd.of cesium iodide, said sheet being .Iaddend.of substantially uniform thickness .Iadd.and being located within said evacuated envelope; .Iaddend. b. said sheet having the following physical properties: i. photoluminescent and transparent to its own light; ii. efficient in absorption of ray energy; iii. of sufficient thickness and absorption to convert to light energy substantial percentages of gamma energy emanating from a source of energy of 250 kev. or less; iv. of high resolution characteristics; and v. dish-shaped in configuration and focused to an accelerating electron field in said tube. .[.2. The image device of claim 1 wherein said sheet
Claim 2
Dependent Claim
14 words
is cesium iodide..].3. The image device of claim 1 wherein said sheet is a
Claim 3
Dependent Claim
14 words
single crystal. .[.4. The image device of claim 1 wherein said sheet is a
Claim 4
Dependent Claim
144 words
single crystal of cesium iodide..]. 5. An image intensification tube responsive to stimulation by gamma energy or the like comprising: a. an evacuated envelope having an input end and an output phosphor spaced therefrom; b. a dish-shaped light-emissive layer near said input end and composed of a single crystalline sheet of photoluminescent material; c. an electron-emissive layer deposited near an inner surface of said light-emissive layer such that light photons emitted by said light-emissive layer stimulate said electron-emissive layer and cause the latter layer to emit electrons; d. means for accelerating electrons from said electron-emissive layer against said output phosphor; e. said dish shape of said light-emissive layer and said electron layer being substantially contoured to the shape of an accelerating electron field produced by said acceleration means so as to be focused therewith, and f. a mounting means supporting said light-emissive layer and
Claim 5
Dependent Claim
144 words
single crystal of cesium iodide..]. 5. An image intensification tube responsive to stimulation by gamma energy or the like comprising: a. an evacuated envelope having an input end and an output phosphor spaced therefrom; b. a dish-shaped light-emissive layer near said input end and composed of a single crystalline sheet of photoluminescent material; c. an electron-emissive layer deposited near an inner surface of said light-emissive layer such that light photons emitted by said light-emissive layer stimulate said electron-emissive layer and cause the latter layer to emit electrons; d. means for accelerating electrons from said electron-emissive layer against said output phosphor; e. said dish shape of said light-emissive layer and said electron layer being substantially contoured to the shape of an accelerating electron field produced by said acceleration means so as to be focused therewith, and f. a mounting means supporting said light-emissive layer and
Claim 6
Dependent Claim
22 words
electron-emissive layer near said input end. 6. The tube of claim 5 wherein said photoluminescent material is a single crystal of cesium
Claim 7
Dependent Claim
13 words
iodide. 7. The tube of claim 5 wherein said photoluminescent material is a
Claim 8
Dependent Claim
11 words
single crystal. 8. The tube of claim 5 wherein said photoluminescent
Claim 9
Dependent Claim
37 words
material is cesium iodide. 9. The tube of claim 5 wherein said photoluminescent material is of sufficient thickness to absorb about 30 percent of source energy of 150 kev. or less and is transparent to its own
Claim 10
Dependent Claim
21 words
light. 10. The tube of claim 5 wherein said photoluminescent material can withstand temperatures of 300° F. without distortion or other
Claim 11
Dependent Claim
35 words
degradation. 11. The tube of claim 5 wherein said mounting means is open at a central portion whereby entering energy passing through said central portion is not filtered or otherwise obstructed by said mounting means.
Claim 12
Independent Claim
125 words
The method of forming an input gamma ray sensitive structure for an image intensification tube comprising the steps of: a. heat softening a single crystal of cesium iodide; b. molding the single crystal of cesium iodide while heat softened to a dish-shaped configuration having a concave output surface to form a photoemissive layer; c. depositing an electron-emissive layer on the output dish of said formed dish-shaped cesium iodide crystal with the electron layer and crystal in sufficiently close juxtaposition that light energy emitted by the crystal stimulates said electron-emissive layer and causes the emission of electrons when in use; and d. securing a mounting means to the periphery of said photoemissive layer and mounting said layers in an envelope with the convex surface of the
Claim 13
Independent Claim
125 words
The method of forming an input gamma ray sensitive structure for an image intensification tube comprising the steps of: a. heat softening a single crystal of cesium iodide; b. molding the single crystal of cesium iodide while heat softened to a dish-shaped configuration having a concave output surface to form a photoemissive layer; c. depositing an electron-emissive layer on the output dish of said formed dish-shaped cesium iodide crystal with the electron layer and crystal in sufficiently close juxtaposition that light energy emitted by the crystal stimulates said electron-emissive layer and causes the emission of electrons when in use; and d. securing a mounting means to the periphery of said photoemissive layer and mounting said layers in an envelope with the convex surface of the
Claim 14
Dependent Claim
70 words
photoemissive layer oriented toward an input end of said envelope. 13. The method of claim 12 wherein the depositing steps is on a barrier layer and including the step of providing a barrier layer between the electron-emissive layer and the crystal. .Iadd. 14. The image-forming device of claim 1 wherein said sheet is of sufficient thickness to absorb approximately thirty percent of source energy at 150 kev. or less. .Iaddend.
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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) | 1979-03-30 | 1979-09-29 | 1980-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-30 | 1983-09-29 | 1984-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-30 | 1987-09-29 | 1988-03-30 | $7700.00 | Window Closed / Lapsed |