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US4866745A
Expired / Lapsed
US
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Ultrahigh speed X-ray CT scanner
Assignee: National Institute of Advanced Industrial Science and Technology
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Filing: 1987-03-30
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Granted: 1989-09-12
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Expires: 2007-03-30
Abstract
Abstract An X-ray CT scanner comprises a plurality of X-ray generators which are arranged radially on a circle concentric with an object for measurement and each consists of a cathode electrode, an anode electrode constituting a target and a grid between the cathode and anode electrodes. For X-ray tomography, X-rays are projected onto the objects from the circle concentric therewith by sequentially temporarily removing a bias voltage applied to the grids of the respective X-ray generators for suppressing an electron beam directed from the cathode electrode to the anode electrode of each X-ray generator.
Inventors
- 👤 Makoto Akai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:49
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/02; A61B6/03; A61B6/032; A61B6/40; A61B6/4021; A61B6/4028; G; G01; G01N; G01N23/00; G01N23/02; G01N23/04; G01N23/046; H; H01; H01J; H01J35/00; H01J35/02; H01J35/04; H05; H05G; H05G1/00; H05G1/08; H05G1/70; G01N2223/00; G01N2223/40; G01N2223/419
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
192 words
An ultrahigh-speed X-ray CT scanner comprising: a substantially semicircular vacuum vessel disposed on a circumference of a circle concentrically surrounding a position for an object for measurement; a plurality of X-ray generators disposed in said vacuum vessel and arranged on the circumference of the circle for projecting X-rays onto said object, each of said X-ray generators including a cathode electrode, a grid, a multi-stage electrode for converging and accelerating an electron beam emitted from said cathode electrode, and an anode electrode constituting a target; means for applying a bias voltage to the grids, means for temporarily removing the bias voltage applied to said grids one after another; and a plurality of X-ray sensors supported by a substantially semicircular support which is disposed on the circumference of the circle at a position where said object intervenes between said sensors and said vacuum vessel, and arranged on the circumference of the circle for receiving the X-rays projected from said X-ray generators wherein each of said x-ray generators includes a beam deflection lens disposed between said multi-stage electrode and said target so as to deflect the electron beam in the axial direction of the object.
Claim 2
Dependent Claim
192 words
An ultrahigh-speed X-ray CT scanner comprising: a substantially semicircular vacuum vessel disposed on a circumference of a circle concentrically surrounding a position for an object for measurement; a plurality of X-ray generators disposed in said vacuum vessel and arranged on the circumference of the circle for projecting X-rays onto said object, each of said X-ray generators including a cathode electrode, a grid, a multi-stage electrode for converging and accelerating an electron beam emitted from said cathode electrode, and an anode electrode constituting a target; means for applying a bias voltage to the grids, means for temporarily removing the bias voltage applied to said grids one after another; and a plurality of X-ray sensors supported by a substantially semicircular support which is disposed on the circumference of the circle at a position where said object intervenes between said sensors and said vacuum vessel, and arranged on the circumference of the circle for receiving the X-rays projected from said X-ray generators wherein each of said x-ray generators includes a beam deflection lens disposed between said multi-stage electrode and said target so as to deflect the electron beam in the axial direction of the object.
Claim 3
Dependent Claim
31 words
The X-ray CT scanner according to claim 1, wherein said target is formed of a film having a thickness equal to or less than the range of the electron beam accelerated.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-09-11 | 1993-03-13 | 1993-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-11 | 1997-03-13 | 1997-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-11 | 2001-03-13 | 2001-09-12 | $7700.00 | Window Closed / Lapsed |