Methods and systems for rapid detection of concealed objects using fluorescence

• US 20060098773A1
• Filed: 10/15/2005
• Published: 05/11/2006
• Est. Priority Date: 09/15/2003
• Status: Active Grant

• Current Assignee: Rapiscan Systems Incorporated (OSI Systems Incorporated)
• Original Assignee: Rapiscan Security Products USA Incorporated (OSI Systems Incorporated)
• Inventors: Peschmann, Kristian R.
• Granted Patent: US 7,366,282 B2
• Time in Patent Office: Days
• US Class Current: 378/57
• CPC Class Codes: G01N 23/04 and forming images of the material

Abstract

This invention is directed towards finding, locating, and confirming threat items and substances. The inspection system is designed to detect objects that are made from, but not limited to, special nuclear materials (“SNM”) and/or high atomic number materials. The system employs advanced image processing techniques to analyze images of an object under inspection (“OUI”), which includes, but is not limited to baggage, parcels, vehicles and cargo, and fluorescence detection.

Claims

1. An apparatus for identifying an object concealed within a container, comprising:

a first stage inspection system having a scanning system to generate a first set of data;

a plurality of processors in data communication with the first stage inspection system wherein the processors process said first set of data and wherein the first set of data is used to identify at least one target region;

a means for positioning an inspection region relative to the target region wherein an inspection region at least partially physically coincides with the target region; and

a second stage inspection system for generating the inspection region wherein the second stage inspection system produces a second set of data having an X-ray signature characteristic of the material in said inspection region and a third set of data having an fluorescence signature characteristic of the material in said inspection region.

2. The apparatus of claim 1 wherein the second stage inspection system is a C-shaped inspection system.

3. The apparatus of claim 1 wherein the second stage inspection system comprises at least one diffraction detector head and at least one fluorescence detector head.

4. The apparatus of claim 1 further comprising a bypass conveyor capable of moving said object into a secured area without first passing through said second stage inspection system.

5. The apparatus of claim 1 wherein an operator selects a region based upon an X-ray characteristic.

6. The apparatus of claim 5 wherein the X-ray characteristic is at least one of mass, degree of attenuation, area, atomic number, size, shape, pattern, or context.

7. The apparatus of claim 1 wherein the target region is identified by having a processor execute an algorithm to select a region based upon said first set of data.

8. The apparatus of claim 1 wherein a plurality of X-ray beam projections intersects the target region at an intersection area, said target region having a location.

9. The apparatus of claim 8 wherein the location of the target region is determined by identifying a set of coordinates for the intersection area.

10. The apparatus of claim 9 wherein a plurality of control commands is produced in response to the determination of said location of the target region.

11. The apparatus of claim 10 wherein the inspection region is positioned relative to the target region in response to the plurality of control commands using a three-axis control system.

12. The apparatus of claim 1 wherein the means for positioning said inspection region relative to the target region includes a plurality of adjustable apertures.

13. The apparatus of claim 12 wherein the apertures can be physically moved in the direction of the main beam axis.

14. The apparatus of claim 13 wherein the aperture is a ring aperture having an adjustable diameter.

15. The apparatus of claim 1 wherein the means for positioning said inspection region relative to the target region comprises a conveyor operable to move in elevation relative to the second stage inspection system.

16. The apparatus of claim 1 wherein the means for positioning said inspection region relative to the target region comprises an aperture and ring aperture.

17. The apparatus of claim 1 wherein the second stage inspection system comprises an inspection region generation system.

18. The apparatus of claim 17 wherein the inspection region generation system comprises a source of X-ray radiation.

19. The apparatus of claim 18 wherein the inspection region generation system comprises an energy dispersive detector.

20. The apparatus of claim 19 wherein the energy dispersive detector is used to produce a signature of the material in the inspection region.

21. The apparatus of claim 18 wherein the inspection region generation system comprises a fluorescence detector.

22. The apparatus of claim 21 wherein the fluorescence detector is used to produce a signature of the material in the inspection region.

23. The apparatus of claim 1 wherein said first set of data is used to identify a reference spectrum.

24. The apparatus of claim 23 wherein said identification of a reference spectrum is achieved by identifying a spectrum associated with said first set of data.

25. The apparatus of claim 24 wherein the reference spectrum is used to correct a diffraction spectrum.

26. The apparatus of claim 24 wherein the reference spectrum is used to correct for beam hardening.

27. The apparatus of claim 1 wherein the X-ray signature characteristic is a diffraction pattern.

28. The apparatus of claim 1 wherein the X-ray signature characteristic is a scatter spectrum.

29. The apparatus of claim 1 wherein the X-ray signature characteristic is an electronic response signal.

30. A method for identifying an object concealed within a container, comprising:

generating a first set of data using a first stage X-ray inspection system;

processing said first set of data using a plurality of processors in data communication with the first stage inspection system;

identifying at least one target region from said processed first set of data;

positioning an inspection region relative to the target region wherein the inspection region at least partially physically coincides with the target region;

generating the inspection region through a second stage inspection system; and

producing a second set of data having a X-ray signature characteristic of the material in the inspection region and a fluorescence signature characteristic of the material in the inspection region.

31. The method of claim 30 wherein an operator identifies at least one target region by selecting a region based upon an X-ray image characteristic.

32. The method of claim 31 wherein the X-ray image characteristic is at least one of mass, degree of attenuation, total area, atomic number, size, shape, or organic to inorganic ratio.

33. The method of claim 30 wherein the location of the target region is determined by identifying a set of coordinates for said target region.

34. The method of claim 33 wherein a plurality of control commands is produced in response to the determination of said location of the target region.

35. The method of claim 34 wherein the inspection region is positioned relative to the target region in response to the plurality of control commands using a three-axis control system.

36. The method of claim 30 wherein the positioning of the inspection region relative to the target region is achieved using a plurality of adjustable apertures.

37. The method of claim 36 wherein the aperture can be physically moved horizontally or vertically.

38. The method of claim 36 wherein the aperture is a ring aperture having an adjustable diameter.

39. The method of claim 30 wherein the positioning of the inspection region relative to the target region is achieved using a conveyor operable to move in elevation relative to the second stage inspection system.

40. The method of claim 30 wherein the positioning of the inspection region relative to the target region is achieved using an aperture and ring aperture.

41. The method of claim 30 wherein the second stage inspection system comprises an energy dispersive detector.

42. The method of claim 41 wherein the energy dispersive detector is used to produce a signature of the material in the inspection region and the first set of data is used to produce data defining at least one of mass, degree of attenuation, area, or average atomic number, of the material in a beampath.

43. The method of claim 30 wherein the second stage inspection system comprises a fluorescence detector.

44. The method of claim 30 wherein a reference spectrum is determined by identifying a spectrum associated with said first set of data.

45. The method of claim 44 wherein the reference spectrum is used to correct a diffraction spectrum.

46. The method of claim 44 wherein the reference spectrum is used to correct for beam hardening.

47. The method of claim 30 wherein the X-ray signature characteristic is a diffraction pattern.

48. The method of claim 30 wherein the X-ray signature characteristic is a scatter spectrum.

49. The method of claim 30 wherein the X-ray signature characteristic is an electronic response signal.

50. A device for inspecting high atomic number material located within a target object using a radiation source, comprising:

a first member having detector electronics and a diffraction detector head;

a second member affixed substantially perpendicularly to the first member;

a third member affixed substantially perpendicularly to the second member and parallel to the first member, wherein the third member comprises a radiation source for projecting an X-ray beam toward the target object and comprises a fluorescence detector head; and

a conveyor for positioning said target object between said first member and said second member.

51. The device of claim 50 wherein said device operates by:

detecting a diffraction signal using a diffraction detector head;

detecting a fluorescence signal using a fluorescence detector head; and

identifying said high atomic number material using said diffraction signal and said fluorescence signal.

52. The device of claim 50 further comprising:

at least one processor and display for generating an image of said target object;

at least one processor having software for analyzing the image using an algorithm to evaluate regions of objects based upon a threshold level;

at least one processor having software for segmenting said image into regions based upon criteria;

at least one processor having software for directing the device to further inspect selected regions satisfying certain criteria to determine their size and shape;

at least one processor having software for comparing said selected regions to threat criteria; and

at least one processor having software for issuing an alarm to an inspector when an object is determined as matching said threat criteria in said comparing step.