X-ray backscatter inspection with coincident optical beam

• US 20060245548A1
• Filed: 04/21/2006
• Published: 11/02/2006
• Est. Priority Date: 04/22/2005
• Status: Abandoned Application

• Current Assignee: American Science and Engineering Incorporated (OSI Systems Incorporated)
• Original Assignee: American Science and Engineering Incorporated (OSI Systems Incorporated)
• Inventors: Schueller, Richard, Callerame, Joseph, Sapp, William Wade Jr., Schubert, Jeffrey
• Application Number:
  US11/409,513
• Publication Number:
  US 20060245548A1
• Time in Patent Office: Days
• US Class Current: 378/160
• CPC Class Codes: G01N 23/203 Measuring back scattering
• CPC Class Codes: G01V 5/0025 Measuring scattered radiation
• CPC Class Codes: G01V 5/222 measuring scattered radiation
• CPC Class Codes: G21K 1/04 using variable diaphragms, shutters, choppers
• CPC Class Codes: G21K 1/043 changing time structure of beams by mechanical means, e.g. choppers, spinning filter wheels

Abstract

Apparatus and methods that permit an operator of a backscatter x-ray system to shine a search light on a closed container or vehicle, and then image the contents of that container in a region roughly corresponding to the area of the container covered by the search light. A display near the operator presents the backscatter image of the container contents.

Claims

1. An inspection system for inspecting an object, the system comprising:

a. a source of penetrating radiation characterized by a range of wavelengths;

b. a spatial modulator for forming the penetrating radiation into a beam of penetrating radiation for irradiating the object with a profile scanned in two dimensions, the object disposed entirely outside the enclosing body;

c. a remote spatial registration mechanism for defining an area at the object substantially contiguous with the profile scanned by the penetrating radiation; and

d. a detector module capable of detecting a scatter signal of penetrating radiation from contents of the object.

2. An inspection system in accordance with claim 1, wherein the spatial modulator includes at least one of a chopper wheel, a rotating stage, and a translating stage.

3. An inspection system in accordance with claim 1, wherein the remote spatial registration mechanism includes a source of electromagnetic radiation at a wavelength distinct from that of the range of wavelengths of the penetrating radiation, for subtending an area at the object substantially contiguous with the profile scanned by the penetrating radiation.

4. An inspection system in accordance with claim 3, wherein the electromagnetic radiation at a wavelength distinct from that of the band of wavelengths of the penetrating radiation is a visible searchlight beam.

5. An inspection system in accordance with claim 1, wherein the remote spatial registration mechanism includes a camera used to define the target area.

6. An inspection system in accordance with claim 1, wherein the source of penetrating radiation is disposed upon a vehicle capable of autonomous road travel.

7. An inspection system in accordance with claim 1, wherein the source of penetrating radiation is disposed upon a conveyance towed by a vehicle.

8. An inspection system in accordance with claim 1, wherein the source of penetrating radiation is chosen from a group including an x-ray tube and a source of gamma rays.

9. An inspection system in accordance with claim 1, wherein the source of penetrating radiation includes one or more rotating chopper wheels with scanning apertures for generating a scanning pencil beam.

10. An inspection system in accordance with claim 1, wherein the source of penetrating radiation includes an aperture that is mechanically moved in a rectilinear fashion along with the x-ray source.

11. An inspection system in accordance with claim 1, wherein the source of penetrating radiation includes an aperture that is mechanically moved in a rotational fashion along with the x-ray source.

12. An inspection system in accordance with claim 1, wherein the source of penetrating radiation includes a plurality of rotating chopper wheels, where the chopper wheels may be interchangeable by automated or other means, in order to permit the field of view to narrowed or widened.

13. An inspection system in accordance with claim 1, wherein the source of penetrating radiation includes one or more interchangeable chopper wheels, the chopper wheels not all having identical aperture sizes.

14. An inspection system in accordance with claim 1, wherein detectors of radiation scattered by the target object are coupled to a conveyance.

15. An inspection system in accordance with claim 1, wherein the detector module of the radiation scattered by the target object is deployed remotely from the source of penetrating radiation.

16. An inspection system in accordance with claim 1, wherein the distance to the object under inspection is determined by one or more sensors chosen from the group of radar, ultrasound, optical, and laser sensors.

17. An inspection system in accordance with claim 1, wherein the distance to the object under inspection is noted on the image screen to help the viewer assess the actual size of the perceived threat.

18. An inspection system in accordance with claim 1, wherein moveable vanes are disposed in front of the detector module to limit radiation received to that scattered from the targeted region.

19. A method for inspecting an object, the method comprising:

a. providing penetrating radiation characterized by a range of wavelengths;

b. forming the penetrating radiation into a beam;

c. scanning the object with a profile in two dimensions;

d. defining an area at the object substantially contiguous with the profile scanned by the penetrating radiation; and

e. detecting a scatter signal of penetrating radiation from contents of the object.

20. A method for inspecting an object in accordance with claim 19, wherein the step of defining an area substantially contiguous with the profile scanned by the penetrating radiation includes illuminating the area with a beam of non-penetrating electromagnetic radiation.