US4392237A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Scanning x-ray inspection system
Assignee: General Electric Co
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Filing: 1980-08-25
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Granted: 1983-07-05
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Expires: 2000-08-25
Abstract
Abstract An x-ray fan beam is caused to impinge upon an object, such as airport luggage or jars of food, as the object moves translationally through the fan beam; after passage through the object, the x-rays are made to impinge upon an x-ray transmissive detector housing containing a gaseous detecting medium, a power electrode and a plurality of signal electrodes. The power electrode and the signal electrode are maintained at different voltage levels so that electrons and/or ions generated by the interaction of the gaseous detecting medium and the x-rays, drift toward the electrodes thereby producing an electrical current which can be sensed, analyzed, and used, for example, to generate an image or to indicate the presence of foreign matter.
Inventors
- 👤 John M. Houston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:49
CPC Classifications
G; G01; G01N; G01N23/00; G01N23/02; G01N23/06; G01N23/10; G01N23/083
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
170 words
An x-ray scanning system for generating signals corresponding to x-ray absorption levels in an object comprising: means for translationally moving said object; x-ray means for subjecting said object to a substantially flat, fan-shaped x-ray beam, said beam being in a plane which does not contain the direction of motion of said object; a detector, said detector having a substantially planar power electrode and a plurality of substantially planar signal electrodes spaced apart from and parallel to said power electrode, said signal electrodes being configured so as to lie in a plane substantially parallel to said power electrode, said power electrode and said signal electrodes being parallel to the plane of said fan-shaped x-ray beam and positioned so that said beam passes between said power electrode and said signal electrodes, all of said electrodes being disposed in an x-ray transmissive housing containing a gaseous detecting medium; means to impress a voltage on said power electrode relative to said signal electrodes; means to sense current passing through each of said signal electrodes.
Claim 2
Dependent Claim
170 words
An x-ray scanning system for generating signals corresponding to x-ray absorption levels in an object comprising: means for translationally moving said object; x-ray means for subjecting said object to a substantially flat, fan-shaped x-ray beam, said beam being in a plane which does not contain the direction of motion of said object; a detector, said detector having a substantially planar power electrode and a plurality of substantially planar signal electrodes spaced apart from and parallel to said power electrode, said signal electrodes being configured so as to lie in a plane substantially parallel to said power electrode, said power electrode and said signal electrodes being parallel to the plane of said fan-shaped x-ray beam and positioned so that said beam passes between said power electrode and said signal electrodes, all of said electrodes being disposed in an x-ray transmissive housing containing a gaseous detecting medium; means to impress a voltage on said power electrode relative to said signal electrodes; means to sense current passing through each of said signal electrodes.
Claim 3
Dependent Claim
65 words
The x-ray scanning system of claim 1 in which said x-ray means comprises: a source of x-rays; and a collimator sheet having a slit, said collimator being positioned between said x-ray source and said object so as to subject said object to a substantially flat, fan-shaped x-ray beam, said beam being in a plane which does not contain the direction of motion of said object.
Claim 4
Dependent Claim
18 words
The x-ray scanning system of claim 1 in which the signal electrodes are parallel, one to the other.
Claim 5
Dependent Claim
28 words
The x-ray scanning system of claim 1 in which said gaseous detecting medium comprises substances of atomic weight greater than or equal to the atomic weight of argon.
Claim 6
Dependent Claim
30 words
The x-ray scanning system of claim 1 in which said gaseous medium comprises material selected from the group consisting of argon, krypton, xenon, and mixtures of argon, krypton, and xenon.
Claim 7
Dependent Claim
24 words
The x-ray scanning system of claim 1 in which said gaseous detecting medium has a pressure between approximately 10 atmospheres and approximately 100 atmospheres.
Claim 8
Dependent Claim
25 words
The x-ray scanning system of claim 1 in which said signal electrodes comprise strips of electrically conductive material disposed on a sheet of dielectric material.
Claim 9
Dependent Claim
31 words
The x-ray scanning system of claim 1 in which said housing is circularly arcuate and said signal electrodes having a long dimension lying substantially along the radii of said circular arc.
Claim 10
Dependent Claim
13 words
The x-ray scanning system of claim 1 in which said housing comprises aluminum.
Claim 11
Dependent Claim
29 words
The x-ray scanning system of claim 1 in which said signal electrodes are parallelograms with a long dimension oriented substantially parallel to the incident direction of said fan beam.
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) | 1986-07-04 | 1987-01-03 | 1987-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-04 | 1991-01-03 | 1991-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-04 | 1995-01-03 | 1995-07-05 | $7700.00 | Window Closed / Lapsed |