US5712926A
Expired / Lapsed
US
⏱️ 0.0 years remaining
X-ray computed tomography (CT) system for detecting thin objects
Assignee: Leidos Security Detection and Automation Inc
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Filing: 1994-10-20
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Granted: 1998-01-27
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Expires: 2014-10-20
Abstract
Abstract A technique to ascertain the presence or absence of an object in a three-dimensional volume, such as explosives in the side walls of luggage. The technique involves radiation scanning the three-dimensional volume to determine a property of each of a plurality of voxels representing the three-dimensional volume and to identify voxels having similar values of the property to identify a contiguous group of voxels having the similar values. Then, the contiguous group of voxels is identified as containing the object if a characteristic (such as mass and/or volume) of the contiguous group has a predetermined value.
Inventors
- 👤 Jeffrey Wayne Eberhard
- 👤 Meng-Ling Hsiao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 13:45
CPC Classifications
G; G01; G01V; G01V5/00; G01V5/20; G01V5/22; G01V5/226; G01N; G01N23/00; G01N23/02; G01N23/04; G01N23/046; G01N2223/00; G01N2223/40; G01N2223/419
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
123 words
A method of detecting an explosive comprising the steps of: (a) scanning a three-dimensional volume to determine the density of each of a plurality of voxels representing the three-dimensional volume; (b) connecting and labeling voxels of the plurality of voxels which have similar densities; (c) determining the volume of each contiguous region of voxels having similar densities; (d) comparing the volume of each such contiguous region to a first threshold and identifying each such contiguous region which exceeds the first threshold as a suspect region; (e) determining the mass of each suspect region; and (f) comparing the mass of each suspect region to a second threshold and identifying each suspect region which exceeds the second threshold as a region potentially containing an explosive.
Claim 2
Independent Claim
123 words
A method of detecting an explosive comprising the steps of: (a) scanning a three-dimensional volume to determine the density of each of a plurality of voxels representing the three-dimensional volume; (b) connecting and labeling voxels of the plurality of voxels which have similar densities; (c) determining the volume of each contiguous region of voxels having similar densities; (d) comparing the volume of each such contiguous region to a first threshold and identifying each such contiguous region which exceeds the first threshold as a suspect region; (e) determining the mass of each suspect region; and (f) comparing the mass of each suspect region to a second threshold and identifying each suspect region which exceeds the second threshold as a region potentially containing an explosive.
Claim 3
Dependent Claim
28 words
A method as set forth in claim 1 further comprising the step of: after step (f), further inspecting the three-dimensional volume to confirm the presence of an explosive.
Claim 4
Dependent Claim
15 words
A method as set forth in claim 2, wherein the further inspection includes manual inspection.
Claim 5
Dependent Claim
15 words
A method as set forth in claim 2, wherein the further inspection includes neutron interrogation.
Claim 6
Independent Claim
143 words
An apparatus to detect an explosive, comprising: (a) a scanner to scan a three-dimensional volume to determine the density of each of a plurality of voxels representing the three-dimensional volume; and (b) a processor which includes (1) a contiguity identification module to connect and label voxels of the plurality of voxels which have similar densities; and (2) an object identification module to (i) determine the volume of each contiguous region of voxels having similar densities; (ii) compare the volume of each such contiguous region to a first threshold and to identify each such contiguous region which exceeds the first threshold as a suspect region; (iii) determine the mass of each suspect region; and (iv) compare the mass of each suspect region to a second threshold and to identify each suspect region which exceeds the second threshold as a region potentially containing an explosive.
Claim 7
Independent Claim
143 words
An apparatus to detect an explosive, comprising: (a) a scanner to scan a three-dimensional volume to determine the density of each of a plurality of voxels representing the three-dimensional volume; and (b) a processor which includes (1) a contiguity identification module to connect and label voxels of the plurality of voxels which have similar densities; and (2) an object identification module to (i) determine the volume of each contiguous region of voxels having similar densities; (ii) compare the volume of each such contiguous region to a first threshold and to identify each such contiguous region which exceeds the first threshold as a suspect region; (iii) determine the mass of each suspect region; and (iv) compare the mass of each suspect region to a second threshold and to identify each suspect region which exceeds the second threshold as a region potentially containing an explosive.
Claim 8
Dependent Claim
42 words
A method as set forth in claim 1, wherein in step (b) differences between a density of a given voxel and densities of voxels in planes above and below said given voxel, are employed to evaluate contiguity of said plurality of voxels.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-01-26 | 2001-07-28 | 2002-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-01-26 | 2005-07-28 | 2006-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-01-26 | 2009-07-28 | 2010-01-27 | $7700.00 | Window Closed / Lapsed |