US4002910A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Radiology
Assignee: QED Intellectual Property Ltd
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Filing: 1975-07-17
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Granted: 1977-01-11
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Expires: 1995-07-17
Abstract
Abstract In a method of constructing a representation of the distribution of absorption in a planar region of a body interpolation is provided, between data signals representing absorption of radiation along parallel paths, to provide signals for an increased number of such paths as required for the processing used. The interpolation is performed by forming differences of second or higher order, subdividing the differences and then combining them by running additions.
Inventors
- 👤 Christopher Archibald Gordon LeMay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:00
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/40; A61B6/4064; A61B6/4071; G; G06; G06T; G06T12/00; G06T12/10; Y; Y10; Y10S; Y10S378/00; Y10S378/901
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
143 words
A method of constructing a representation of the distribution of absorption in a planar region of a body including the steps of providing data signals representing the absorption of the radiation along a plurality of substantially parallel paths in the plane of the said region, interpolating between the said data signals to provide further data signals representing the absorption of the radiation along an increased number of such paths and allocating, to each of a plurality of predetermined points in a field notionally delineated in the said region, the data signal or further data signal associated with the path whose centreline passes closest to that point, wherein the interpolation is achieved by forming signals representing difference of said data extending to order m, where m is at least two, subdividing some of said difference signals and combining the subdivided differences by running addition.
Claim 2
Independent Claim
143 words
A method of constructing a representation of the distribution of absorption in a planar region of a body including the steps of providing data signals representing the absorption of the radiation along a plurality of substantially parallel paths in the plane of the said region, interpolating between the said data signals to provide further data signals representing the absorption of the radiation along an increased number of such paths and allocating, to each of a plurality of predetermined points in a field notionally delineated in the said region, the data signal or further data signal associated with the path whose centreline passes closest to that point, wherein the interpolation is achieved by forming signals representing difference of said data extending to order m, where m is at least two, subdividing some of said difference signals and combining the subdivided differences by running addition.
Claim 3
Dependent Claim
21 words
A method according to claim 1 wherein the interpolation is based soley on the combination of subdivided differences of order m.
Claim 4
Dependent Claim
12 words
A method according to claim 1 wherein m has the value 2.
Claim 5
Dependent Claim
34 words
A method to claim 1 wherein n subdivided values are provided for each m th order difference value to be so subdivided, each being equal to the respective difference divided by n m .
Claim 6
Independent Claim
149 words
An apparatus for constructing a representation of the distribution of absorption in a planar region of a body including means for providing data signals representing the absorption of the radiation along a plurality of substantially parallel paths in the plane of the said region, means for forming signals representing differences of said data extending to order m, where m is at least two, means for subdividing some of said difference signals and combining the subdivided differences by running addition to provide further data signals representing the absorption of the radiation along an increased number of paths, storage means having a plurality of locations associated with a plurality of predetermined points in a field notionally delineated in the said region and means for allocating of each of said locations the data signal or further data signal associated with path whose centreline passes closest to the point associated with that location.
Claim 7
Independent Claim
149 words
An apparatus for constructing a representation of the distribution of absorption in a planar region of a body including means for providing data signals representing the absorption of the radiation along a plurality of substantially parallel paths in the plane of the said region, means for forming signals representing differences of said data extending to order m, where m is at least two, means for subdividing some of said difference signals and combining the subdivided differences by running addition to provide further data signals representing the absorption of the radiation along an increased number of paths, storage means having a plurality of locations associated with a plurality of predetermined points in a field notionally delineated in the said region and means for allocating of each of said locations the data signal or further data signal associated with path whose centreline passes closest to the point associated with that location.
References Cited (Backward Citations)
US3778614A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-11 | 1980-07-12 | 1981-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-11 | 1984-07-12 | 1985-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-11 | 1988-07-12 | 1989-01-11 | $7700.00 | Window Closed / Lapsed |