Patent US5241576A successfully refreshed from Google Patents.
US5241576A
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Segmented detector containing sub-elements for separate measuring of a fan beam
Assignee: General Electric Co
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Filing: 1991-12-23
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Granted: 1993-08-31
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Expires: 2011-12-23
Abstract
Abstract An x-ray CT system includes an array of detector elements which measure the attenuation values of a fan beam. Each detector element is comprised of a set of sub-elements disposed in the slice thickness direction. Attenuation signals from the sub-elements are separately preprocessed and summed together to measure the selected slice thickness and avoid partial volume artifacts in the reconstructed image.
Inventors
- 👤 Albert H. R. Lonn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:40
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/29; G01T1/2914; G01T1/2985; Y; Y10; Y10S; Y10S378/00; Y10S378/901
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
150 words
An x-ray CT scanner which comprises: means for producing an x-ray beam which passes through an aperture and has a width in the plane of an image to be produced and a thickness orthogonal to the plane of the image; detector means mounted to intercept the x-ray beam and including a set of detector sub-elements which are disposed along the beam thickness direction and which intercept successive portions of the x-ray beam along its thickness direction to produce a corresponding set of thin slice attenuation signals; preprocessor means including: a) logarithm means for receiving each of the thin slice attenuation signals and producing a corresponding set of logarithmic thin slice attenuation signals; and b) means for summing together the separate logarithmic thin slice attenuation signals to produce a single slice attenuation signal; and image reconstruction means for receiving the single slice attenuation signal and using it to produce an image.
Claim 2
Dependent Claim
150 words
An x-ray CT scanner which comprises: means for producing an x-ray beam which passes through an aperture and has a width in the plane of an image to be produced and a thickness orthogonal to the plane of the image; detector means mounted to intercept the x-ray beam and including a set of detector sub-elements which are disposed along the beam thickness direction and which intercept successive portions of the x-ray beam along its thickness direction to produce a corresponding set of thin slice attenuation signals; preprocessor means including: a) logarithm means for receiving each of the thin slice attenuation signals and producing a corresponding set of logarithmic thin slice attenuation signals; and b) means for summing together the separate logarithmic thin slice attenuation signals to produce a single slice attenuation signal; and image reconstruction means for receiving the single slice attenuation signal and using it to produce an image.
Claim 3
Dependent Claim
49 words
The x-ray CT scanner as recited in claim 1 in which the x-ray beam is a fan beam and the detector means includes a plurality of detector elements disposed in the plane of the fan beam, and each detector element is comprised of a set of said detector sub-elements.
Claim 4
Dependent Claim
49 words
The x-ray CT scanner as recited in claim 2 in which there is a separate preprocessor means for each detector element and each preprocessor means produces a separate single slice attenuation signal by summing the logarithm of the separate thin slice attenuation signals produced by the detector element's sub-elements.
Claim 5
Dependent Claim
36 words
The x-ray CT scanner as recited in claim 1 in which the preprocessor means includes means for weighting the separate thin slice attenuation signals before they are summed together to form the single slice attenuation signal.
Claim 6
Dependent Claim
41 words
The x-ray CT scanner as recited in claim 1 in which the means for summing the separate logarithmic thin slice attenuation signals produces a plurality of single slice attenuation signals, and the image reconstruction means produces a corresponding plurality of images.
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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) | 1996-08-30 | 1997-03-01 | 1997-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-08-30 | 2001-03-01 | 2001-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-08-30 | 2005-03-01 | 2005-08-31 | $7700.00 | Window Closed / Lapsed |