US4140900A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Panel type x-ray image intensifier tube and radiographic camera system
Assignee: Diagnostic Information Inc
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Filing: 1977-11-21
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Granted: 1979-02-20
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Expires: 1997-11-21
Abstract
Abstract A panel shaped, proximity type, x-ray image intensifier tube for medical x-ray diagnostic use having all linear components and yet a high brightness gain, in the range of 500 to 20,000 cd-sec/m 2 -R, the tube being comprised of a rugged metallic tube envelope, an inwardly concave, iron, nickel, chromium alloy input window, a full size output display screen, a halide activated alkaline-halide scintillator photocathode screen suspended on insulators within the envelope and in between the input window and the output screen, and a high Z glass output window to reduce x-ray backscatter inside and outside of the tube. The tube can be used in a direct view, photofluorographic mode, in a radiographic camera system and with a remote view T.V. system.
Inventors
- 👤 Shih-Ping Wang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:21
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/36; H01J29/38; H01J29/385; H01J31/00; H01J31/08; H01J31/50; H01J31/505
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
98 words
An x-ray sensitive image intensifier tube comprising a tube envelope, a metallic input window in the tube envelope, the input window being made of an alloy of iron, chromium and nickel, a flat scintillator screen adjacent the input window, a flat photocathode layer parallel and immediately adjacent to the scintillator screen, a flat, phosphor display screen parallel to and spaced apart from the photocathode layer, and means for connecting an external source of high voltage between the photocathode layer and the output display screen, and wherein the tube envelope houses the scintillator screen, photocathode layer and display screen.
Claim 2
Dependent Claim
98 words
An x-ray sensitive image intensifier tube comprising a tube envelope, a metallic input window in the tube envelope, the input window being made of an alloy of iron, chromium and nickel, a flat scintillator screen adjacent the input window, a flat photocathode layer parallel and immediately adjacent to the scintillator screen, a flat, phosphor display screen parallel to and spaced apart from the photocathode layer, and means for connecting an external source of high voltage between the photocathode layer and the output display screen, and wherein the tube envelope houses the scintillator screen, photocathode layer and display screen.
Claim 3
Dependent Claim
47 words
An x-ray sensitive image intensifier tube as recited in claim 1, wherein the phosphor display screen comprises a planar high Z glass window in the tube envelope and a phosphor layer on the planar surface of the window which is interior with respect to the tube envelope.
Claim 4
Dependent Claim
47 words
An x-ray sensitive image intensifier tube as recited in claim 1, wherein the tube envelope is metallic and includes a collar of iron-nickel alloy which is fritted to the output window and is welded to the tube envelope for mounting the output window in the tube envelope.
Claim 5
Dependent Claim
42 words
An x-ray sensitive image intensifier tube as recited in claim 1 further comprising a source of high voltage for applying, through the connecting means, a field potential between the photocathode layer and the display screen of between 2 Kv/mm and 5 Kv/mm.
Claim 6
Dependent Claim
26 words
An x-ray sensitive image intensifier tube as recited in claim 1, wherein the scintillator screen includes a vapor deposited layer of sodium activated, cesium iodide (CsI(Na)).
Claim 7
Dependent Claim
21 words
An x-ray sensitive image intensifier tube as recited in claim 5, wherein the CsI(Na) layer is between 200μ and 600μ thick.
Claim 8
Dependent Claim
26 words
An x-ray sensitive image intensifier tube as recited in claim 1, wherein the scintillator screen includes a vapor deposited layer of calcium tungstate (CaWO 4 ).
Claim 9
Dependent Claim
27 words
An x-ray sensitive image intensifier tube as recited in claim 1, wherein the input window is made of 17-7 PH type of precipitation hardened, chromium-nickel stainless steel.
Claim 10
Dependent Claim
38 words
An x-ray sensitive image intensifier tube as recited in claim 1, wherein the spacing between the photocathode screen and the output display screen is at least 6 mm and the potential between them is at least 15 Kv.
Claim 11
Dependent Claim
20 words
An x-ray sensitive image intensifier tube as recited in claim 1 further comprising means for photographing the output display screen.
References Cited (Backward Citations)
US3681606A
Cited
US4002938A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-19 | 1982-08-21 | 1983-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-19 | 1986-08-21 | 1987-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-19 | 1990-08-21 | 1991-02-20 | $7700.00 | Window Closed / Lapsed |