EP0455177A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
High-speed scan type X-ray generator
Assignee: Shimadzu Corp
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Filing: 1991-04-27
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Granted: —
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Expires: 2011-04-27
Abstract
Abstract A high-speed scan type X-ray generating apparatus for scanning X-ray generating positions along a circumference of an examinee, in which an electron beam is emitted from an electron gun into a ring-shaped vacuum tube. The electron beam is deflected by electromagnets or the like to run on a circular orbit through the vacuum tube. The electron beam is further deflected by different, small electromagnets to deviate from the circular orbit and impinge on a ring-shaped target, thereby generating an X-ray toward the center of the vacuum tube. By controlling the small electromagnets, the X-ray generating position is caused to scan at high speed along a circumferential wall of the ring-shaped target.
Inventors
- 👤 Masatoshi Asari
- 👤 Shiro Oikawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 09:40
CPC Classifications
H; H05; H05G; H05G1/00; H05G1/08; H05G1/70; H01; H01J; H01J35/00; H01J35/02; H01J35/14; H01J35/153; H01J35/24; H01J35/30
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
92 words
A high-speed scan type X-ray generating apparatus for scanning X-ray generating positions along a circumference of an examinee, comprising; a ring-shaped vacuum tube, an electron gun for emitting an electron beam as accelerated into said vacuum tube, first deflecting means for causing said electron beam to run on a ring-shaped orbit through said vacuum tube, second deflecting means for causing said electron beam to deviate from said ring-shaped orbit, and a target for generating X-rays toward center of said vacuum tube when said electron beam deviating from said ring-shaped orbit impinges thereon.
Claim 2
Dependent Claim
130 words
An apparatus as claimed in claim 1, wherein; said first deflecting means includes a pair of ring-shaped magnets opposed to each other across said vacuum tube for generating a magnetic field perpendicular to a plane formed by said ring-shaped vacuum tube, said second deflecting means includes at least one pair of small electromagnets disposed in spaces between opposite pole faces of said magnets and said vacuum tube for generating a magnetic field opposite to said magnetic field formed by said magnets to cause said electron beam to deviate radially outwardly from said ring-shaped orbit, and said target is a ring-shaped target having an inside peripheral wall for generating the X-rays toward the center of said vacuum tube when said electron beam deviating radially outwardly from said ring-shaped orbit impinges thereon.
Claim 3
Dependent Claim
136 words
An apparatus as claimed in claim 1, wherein; said first deflecting means includes a pair of ring-shaped magnets opposed to each other across said vacuum tube for generating a magnetic field perpendicular to a plane formed by said ring-shaped vacuum tube, said second deflecting means includes at least one pair of small electromagnets opposed to one another across and radially of said vacuum tube for generating a magnetic field opposite to said magnetic field formed by said magnets to cause said electron beam to deviate in a direction intersecting said plane formed by said vacuum tube, and said target is a ring-shaped target having a wedge-shaped section for generating the X-rays toward the center of said vacuum tube when said electron beam deviating in the direction intersecting said plane formed by said vacuum tube impinges thereon.
Claim 4
Dependent Claim
83 words
An apparatus as claimed in claim 1, wherein; said first deflecting means includes a pair of ring-shaped magnets opposed to each other across said vacuum tube for generating a magnetic field perpendicular to a plane formed by said ring-shaped vacuum tube, said second deflecting means includes a ring-shaped fixed cathode and a ring-shaped grid mounted inside said ring-shaped vacuum tube, said ring-shaped grid being applied with variable voltages, and said target is a ring-shaped target opposed to said fixed cathode across said grid.
Claim 5
Dependent Claim
53 words
An apparatus as claimed in claim 1, wherein said first deflecting means and second deflecting means include plural pairs of divided electromagnets opposed to one another across said vacuum tube and switchable on and off independently of one another for generating magnetic fields perpendicular to a plane formed by said ring-shaped vacuum tube.
Claim 6
Dependent Claim
23 words
An apparatus as claimed in claim 1, wherein said ring-shaped vacuum tube contains at least one accelerating electrode for accelerating said electron beam.
Claim 7
Dependent Claim
39 words
An apparatus as claimed in claim 2 or 3, wherein the opposite pole faces of the pair of magnets constituting said first deflecting means are inclined to diverge from each other toward the center of said ring-shaped vacuum tube.
Claim 8
Dependent Claim
34 words
An apparatus as claimed in claim 7, wherein said opposite pole faces of said magnets define hills and valleys arranged in a direction of travel of said electron beam and opposed to one another.
Claim 9
Dependent Claim
31 words
An apparatus as claimed in claim 7, further comprising a plurality of magnets arranged between said opposite pole faces of said magnets and having polarities alternately reversed in a circumferential direction.
References Cited (Backward Citations)
No citation records indexed.
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