US5369268A
Expired / Lapsed
US
⏱️ 0.0 years remaining
X-ray detector with charge pattern read-out by TFT switching matrix
Assignee: US Philips Corp
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Filing: 1994-02-15
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Granted: 1994-11-29
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Expires: 2014-02-15
Abstract
Abstract An X-ray image amplifier tube designed with an input screen having a photocathode and with a detection screen which is opposite the latter and a short distance away for detection of a photo-electron beam which is generated by X-ray input image signals and is amplified in the tube. The detection screen is provided with a conversion coating for converting an image-carrying photo-electron beam into a potential excursion and to this end contains, for example, an amorphous selenium coating or a porous KCl coating. A variable potential can be applied both over the vacuum gap between the photocathode and the conversion coating and over the conversion coating itself and, as a result of this, high image brightness dynamics can be achieved without image disruption.
Inventors
- 👤 Gerardus van Aller
- 👤 Ulrich Schiebel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:36
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/08; H01J31/50; H01J31/506; H01J31/507; G; G01; G01T; G01T1/00; G01T1/16; G01T1/28; H01J2231/00; H01J2231/50; H01J2231/50005; H01J2231/5001; H01J2231/50031; H01J2231/50036; H01J2231/50057; H01J2231/50068
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
106 words
An X-ray detector comprising a vacuum-tight casing within which an input screen and an output screen are contained, said input screen having a luminescent layer for producing light radiation in response to incident X-ray radiation and a photocathode layer for producing photoelectrons in response to the light radiation produced by said luminescent layer, and said output screen being positioned relative to said input screen for receiving incident electrons resulting from the photoelectrons produced by the photocathode layer and having a conversion layer for converting said incident electrons into an electric charge pattern, and a switching matrix fixedly positioned for direct readout of said electric charge pattern.
Claim 2
Dependent Claim
106 words
An X-ray detector comprising a vacuum-tight casing within which an input screen and an output screen are contained, said input screen having a luminescent layer for producing light radiation in response to incident X-ray radiation and a photocathode layer for producing photoelectrons in response to the light radiation produced by said luminescent layer, and said output screen being positioned relative to said input screen for receiving incident electrons resulting from the photoelectrons produced by the photocathode layer and having a conversion layer for converting said incident electrons into an electric charge pattern, and a switching matrix fixedly positioned for direct readout of said electric charge pattern.
Claim 3
Dependent Claim
45 words
An X-ray detector as claimed in claim 1, wherein said input and output screens are separated by a gap and further comprising electrode means for receiving a potential difference for accelerating, within said gap, said photoelectrons produced by said photocathode layer toward said output screen.
Claim 4
Dependent Claim
26 words
An X-ray detector as claimed in claim 2, wherein said electrode means is configured for applying said potential difference to said gap via said conversion layer.
Claim 5
Dependent Claim
17 words
An X-ray detector as claimed in claim 1, wherein the conversion layer substantially consists of amorphous selenium.
Claim 6
Dependent Claim
42 words
An X-ray detector as claimed in claim 4, wherein said conversion layer has been formed by vapor deposition of a coating of said amorphous selenium over a surface of said output screen, said coating having has a thickness of about 50 μm.
Claim 7
Dependent Claim
17 words
An X-ray detector as claimed in claim 1, wherein the conversion layer substantially consists of porous KCl.
Claim 8
Dependent Claim
32 words
An X-ray detector as claimed in claim 6, wherein the conversion layer substantially consisting of porous KCl has a porosity corresponding to a fill factor of up to at most about 10%.
Claim 9
Dependent Claim
17 words
An X-ray detector as claimed in claim 2, wherein the conversion layer substantially consists of amorphous selenium.
Claim 10
Dependent Claim
17 words
An X-ray detector as claimed in claim 3, wherein the conversion layer substantially consists of amorphous selenium.
Claim 11
Dependent Claim
42 words
An X-ray detector as claimed in claim 8, wherein said conversion layer has been formed by vapor deposition of a coating of said amorphous selenium over a surface of said output screen, said coating having has a thickness of about 50 μm.
Claim 12
Dependent Claim
42 words
An X-ray detector as claimed in claim 9, wherein said conversion layer has been formed by vapor deposition of a coating of said amorphous selenium over a surface of said output screen, said coating having has a thickness of about 50 μm.
Claim 13
Dependent Claim
17 words
An X-ray detector as claimed in claim 2, wherein the conversion layer substantially consists of porous KCl.
Claim 14
Dependent Claim
17 words
An X-ray detector as claimed in claim 3, wherein the conversion layer substantially consists of porous KCl.
Claim 15
Dependent Claim
32 words
An X-ray detector as claimed in claim 12, wherein the conversion layer substantially consisting of porous KCl has a porosity corresponding to a fill factor of up to at most about 10%.
Claim 16
Dependent Claim
32 words
An X-ray detector as claimed in claim 13, wherein the conversion layer substantially consisting of porous KCl has a porosity corresponding to a fill factor of up to at most about 10%.
Claim 17
Dependent Claim
17 words
An X-ray detector as claimed in claim 1, wherein said switching matrix is a TFT switching matrix.
Claim 18
Dependent Claim
141 words
An X-ray examination apparatus comprising an X-ray source for irradiating an examination area and an X-ray detector for receiving X-ray radiation exiting said examination area as a result said irradiating and being incident upon said detector, said detector comprising a vacuum-tight casing within which an input screen and an output screen are contained, said input screen having a luminescent layer for producing light radiation in response to incident X-ray radiation and a photocathode layer for producing photoelectrons in response to the light radiation produced by said luminescent layer, and said output screen being positioned relative to said input screen for receiving incident electrons resulting from the photoelectrons produced by the photocathode layer and having a conversion layer for converting said incident electrons into an electric charge pattern, and a switching matrix fixedly positioned for direct readout of said electric charge pattern.
Claim 19
Dependent Claim
141 words
An X-ray examination apparatus comprising an X-ray source for irradiating an examination area and an X-ray detector for receiving X-ray radiation exiting said examination area as a result said irradiating and being incident upon said detector, said detector comprising a vacuum-tight casing within which an input screen and an output screen are contained, said input screen having a luminescent layer for producing light radiation in response to incident X-ray radiation and a photocathode layer for producing photoelectrons in response to the light radiation produced by said luminescent layer, and said output screen being positioned relative to said input screen for receiving incident electrons resulting from the photoelectrons produced by the photocathode layer and having a conversion layer for converting said incident electrons into an electric charge pattern, and a switching matrix fixedly positioned for direct readout of said electric charge pattern.
Claim 20
Dependent Claim
46 words
An X-ray examination apparatus as claimed in claim 17, wherein said input and output screens are separated by a gap and further comprising electrode means for receiving a potential difference for accelerating, within said gap, said photoelectrons produced by said photocathode layer toward said output screen.
Claim 21
Dependent Claim
27 words
An X-ray examination apparatus as claimed in claim 18, wherein said electrode means is configured for applying said potential difference to said gap via said conversion layer.
Claim 22
Dependent Claim
18 words
An X-ray examination apparatus as claimed in claim 17, wherein said switching matrix is a TFT switching matrix.
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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) | 1997-11-28 | 1998-05-30 | 1998-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-28 | 2002-05-30 | 2002-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-28 | 2006-05-30 | 2006-11-29 | $7700.00 | Window Closed / Lapsed |