← Back to Patent Explorer
US4211926A Expired / Lapsed US ⏱️ 0.0 years remaining

Tomographic imaging system

Assignee: Hitachi Healthcare Manufacturing Ltd
•
Filing: 1978-04-28
•
Granted: 1980-07-08
•
Expires: 1998-04-28
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In a system in which the tomographic image of an object under investigation is produced on the basis of the amount of absorption of radiation by the object when a source of radiation and a plurality of radiation sensitive detectors with the object interposed therebetween are rotated around the object, the output signal from at least one of the plural detectors is used to correct the radiation absorption amount. Another selected one of the plural detectors may be used for checking whether the object is positioned within a useful detection view.

Inventors

  • 👤 Chitose Nakaya
  • 👤 Hideki Kohno
  • 👤 Hidemi Shiono
  • 👤 Kensuke Sekihara
  • 👤 Shinji Yamamoto
  • 👤 Teruichi Tomura
  • 👤 Takayuki Hayakawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 15:46
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/02; A61B6/03; A61B6/032

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 193 words
A tomographic imaging system comprising: generating means for generating penetrating radiation toward an object under investigation; detecting means including an array of radiation sensitive detectors for detecting the radiation from said generating means transmitted through the object and for providing an output indicative thereof, said detecting means including at at least one side of said detector array of radiation sensitive detectors, a checking detector being responsive to the radiation generated by said generating means which normally does not pass through the object under investigation for checking whether the object is positioned within a field of view of said detector array of radiation sensitive detectors, said checking detector providing an output indicative of the radiation generated which normally does not pass through the object; means for comparing the output of said checking detector with a predetermined value for determining whether the object is positioned within the field of view of said detector array; means for rotating said generating means and said detecting means while keeping a predetermined relative relationship in position with respect to each other; and means for processing the output from said detector array to produce a tomographic image of the object.
Claim 2
Dependent Claim 193 words
A tomographic imaging system comprising: generating means for generating penetrating radiation toward an object under investigation; detecting means including an array of radiation sensitive detectors for detecting the radiation from said generating means transmitted through the object and for providing an output indicative thereof, said detecting means including at at least one side of said detector array of radiation sensitive detectors, a checking detector being responsive to the radiation generated by said generating means which normally does not pass through the object under investigation for checking whether the object is positioned within a field of view of said detector array of radiation sensitive detectors, said checking detector providing an output indicative of the radiation generated which normally does not pass through the object; means for comparing the output of said checking detector with a predetermined value for determining whether the object is positioned within the field of view of said detector array; means for rotating said generating means and said detecting means while keeping a predetermined relative relationship in position with respect to each other; and means for processing the output from said detector array to produce a tomographic image of the object.
Claim 3
Dependent Claim 24 words
A tomographic imaging system according to claim 1, wherein each radiation sensitive detector in said detector array is a gas chamber type of detector.
Claim 4
Dependent Claim 20 words
A tomographic imaging system according to claim 1, further comprising display means for displaying the output from said checking detector.
Claim 5
Dependent Claim 21 words
A tomographic imaging system according to claim 1, wherein a checking detector is provided at each side of said detector array.
Claim 6
Dependent Claim 33 words
A tomographic imaging system according to claim 1, wherein said detector array further includes a detector for producing an output signal for correction of the output of selected detectors of said detector array.

References Cited (Backward Citations)

US3778614A Cited
US3965357A Cited
US4070707A Cited
US4112397A Cited
US4158776A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-07-08 1984-01-07 1984-07-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-07-08 1988-01-07 1988-07-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-07-08 1992-01-07 1992-07-08 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag