Patent US373580A successfully refreshed from Google Patents.
EP0200374A2
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Shadowgraph imaging
Assignee: Philips Nuclear Medicine Inc
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Filing: 1986-04-02
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Granted: —
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Expires: 2006-04-02
Abstract
Abstract @ A method and apparatus for obtaining shadowgraph images suitable for use in computed tomography scanner apparatus for subject localization. A source (20) of radiation that orbits the subject during a normal computed tomography scan is fixed relative an array of radiation detectors (28). The subject is then moved in a direction generally perpendicular to the plane of source (20) and array (28) to obtain a first shadowgraph data set. The source (20) is then orbited a small amount and the subject is again moved relative the source (20) and detector array - (28) to obtain a second shadowgraph set of data. The two sets of data are then interleaved to obtain a shadowgraph image having higher resolution than either the first or second shadowgraph.
Inventors
- 👤 Gordon D. Demeester
- 👤 Rodney A. Mattson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 22:24
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/04; A61B6/0487; A61B6/02; A61B6/03; A61B6/032; A61B6/42; A61B6/4275; Y; Y10; Y10S; Y10S378/00; Y10S378/901
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
95 words
A method of obtaining shadowgraph image data relating to a subject wherein: radiaton from a radiaton source (20) is directed through the subject to an array of radiation detectors (28); and data is obtained representing the radiation reaching said array (28) through said subject as said subject is moved relative to said source (20) and said array - (28); characterised in that data is obtained during two corresponding movements of said subject relative to said source (20) and said array (25); and said data for the two movements are combined to produce said image data.
Claim 2
Independent Claim
95 words
A method of obtaining shadowgraph image data relating to a subject wherein: radiaton from a radiaton source (20) is directed through the subject to an array of radiation detectors (28); and data is obtained representing the radiation reaching said array (28) through said subject as said subject is moved relative to said source (20) and said array - (28); characterised in that data is obtained during two corresponding movements of said subject relative to said source (20) and said array (25); and said data for the two movements are combined to produce said image data.
Claim 3
Dependent Claim
19 words
A method according to Claim 1 wherein said two movements are movements in opposite directions along the same path.
Claim 4
Dependent Claim
66 words
A method according to Claim 1 or Claim 2 wherein the said radiation is directed along trajectories through said subject during one said movement which are different from the trajectories during the other said movement; and said data for the two movements are combined by interleaving so as to provide image data of greater resolution than that given by the data for either one movement alone.
Claim 5
Dependent Claim
36 words
A method according to Claim 3 wherein said different trajectories are obtained by positioning said source (20) at a different angular position (S1, S2) about the direction of said movements during each of said two movements.
Claim 6
Dependent Claim
34 words
A method according to Claim 4 wherein said array (28) is a circular array and said different angular positions (S1, S2) lie on a circular path having the same centre as said array (28).
Claim 7
Dependent Claim
38 words
A method according to Claim 5 wherein the angular position (S1, S2) of said source (20) during said two movements differ by an angle (-y) approximately one half of the angular spacing between adjacent detectors in said array.
Claim 8
Dependent Claim
24 words
A method according to Claim 1 wherein said data for the two movements are subtracted one from the other to obtain contrast image data.
Claim 9
Independent Claim
37 words
A method according to any one of the preceding claims wherein said source (20) and said array - (28) are positioned around an aperture (30) and said movements are in a direction axial of said aperture (30).
Claim 10
Independent Claim
38 words
A method according to any one of the preceding claims wherein during each said movement data is obtained for each of a number of discrete positions of said subject relative to said source (20) and said array (28).
Claim 11
Independent Claim
31 words
A method according to any one of the preceding claims wherein said movements are effected by moving said subject whilst said array (28) and said source (20) remain fixed in position.
Claim 12
Independent Claim
18 words
A method according to any one of the preceding claims wherein said source (20) is an X-ray source.
Claim 13
Independent Claim
47 words
A method according to any one of the preceding claims wherein said method is carried out using a computed tomography scanner apparatus (10), said source (20) and said array (28) being a source and array used to produce computed tomography scans in use of said apparatus (10).
Claim 14
Independent Claim
163 words
An apparatus for producing a shadowgraph image of a subject comprising: a radiation source - (20); an array of radiation detectors (28); means - (22, 24) positioning said source (20) and array (28) so as to direct radiation through said subject onto said array (28); means (12, 24, 50 to 62, 82 to 94) for moving said subject relative to said source (20) and said array (28); means (40) for producing sig; nals representing the radiation reaching said array - (28) from the source (20) through said subject as said subject is moved relative to said source (20) and said array (28); and means (40) for utilising said signals to construct said image; characterised in that said means (12, 24, 50 to 62, 82 to 94) for moving comprises means for carrying out two corresponding movements of said subject relative to said source (20) and said array (28); and said means (40) for utilising combines the said signals produced during both said movements.
Claim 15
Independent Claim
163 words
An apparatus for producing a shadowgraph image of a subject comprising: a radiation source - (20); an array of radiation detectors (28); means - (22, 24) positioning said source (20) and array (28) so as to direct radiation through said subject onto said array (28); means (12, 24, 50 to 62, 82 to 94) for moving said subject relative to said source (20) and said array (28); means (40) for producing sig; nals representing the radiation reaching said array - (28) from the source (20) through said subject as said subject is moved relative to said source (20) and said array (28); and means (40) for utilising said signals to construct said image; characterised in that said means (12, 24, 50 to 62, 82 to 94) for moving comprises means for carrying out two corresponding movements of said subject relative to said source (20) and said array (28); and said means (40) for utilising combines the said signals produced during both said movements.
Claim 16
Dependent Claim
97 words
An apparatus according to Claim 13 wherein said means (22,24) for -positioning includes means (22) for moving said source (20) relative to said subject and said array (28) between said movements so that the said radiation is directed along trajectories through said subject during one said movement which are different from the trajectories during the other said movement; and said means - (40) for utilising combines the signals produced during said two movements by interleaving so as to construct an image of greater resolution than that given by the signals produced during either one said movement alone.
Claim 17
Dependent Claim
38 words
An apparatus according to Claim 14 wherein said means (22) for moving said source (20) comprises means (22) for moving said source (20) to different positions (S1, S2) along a circular path around the direction of said movements.
Claim 18
Dependent Claim
22 words
An apparatus according to Claim 15 wherein said array (28) is a circular array having the same centre as said circular path.
Claim 19
Dependent Claim
45 words
An apparatus according to Claim 13 wherein said means (40) for utilising comprises means (40) for subtracting the said signals produced during one said movement from the said signals produced during the other said movement so as to construct a contrast image of said subject.
Claim 20
Independent Claim
39 words
An apparatus according to any one of Claims 13 to 17 wherein said source (20) and said array - (28) are positioned around a circular aperture (30) and said movements are in a direction axial of said aperture (30).
Claim 21
Independent Claim
34 words
An apparatus according to any one of Claims 13 to 18 wherein said source (20) and said array - (28) are a radiation source and detector array of a computed tomography scanner apparatus (10).
References Cited (Backward Citations)
EP0041752A1
Cited
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