X-ray backscatter mobile inspection van

• US 7,218,704 B1
• Filed: 09/29/2005
• Issued: 05/15/2007
• Est. Priority Date: 11/06/2002
• Status: Expired due to Term

• Current Assignee: American Science and Engineering Incorporated (OSI Systems Incorporated)
• Original Assignee: American Science and Engineering Incorporated (OSI Systems Incorporated)
• Inventors: Grodzins, Lee, Rothschild, Peter, Adams, William L., Chalmers, Alex, Perich, Louis W.
• Primary Examiner(s): Glick; Edward J.
• Assistant Examiner(s): KAO, CHIH CHENG G
• Application Number:
  US11/238,719
• Time in Patent Office: 593 Days
• Field of Search: 378/57, 378/44, 378/45, 378/63, 378/86, 378/87, 378/88, 378/114, 378/115, 378/116
• US Class Current: 378/57
• CPC Class Codes: G01T 3/06 with scintillation detectors
• CPC Class Codes: G01V 5/222 measuring scattered radiation
• CPC Class Codes: G01V 5/232 having relative motion between the source, detector and object other than by conveyor G01V5/226 takes precedence
• CPC Class Codes: G01V 5/26 Passive interrogation, i.e. by measuring radiation emitted by objects or goods

Abstract

An inspection system based upon an enclosed conveyance such as a van, capable of road travel, for inspecting persons or objects. The conveyance is characterized by an enclosing body, or skin. A source of penetrating radiation and a spatial modulator for forming the penetrating radiation into a beam, both contained entirely within the body of the enclosed conveyance, irradiate the person or object with a time-variable scanning profile. A detector module generates a scatter signal based on the scatter of penetrating radiation. A proximity sensor may be employed to generate a relative motion signal based on a relative disposition of the conveyance and the inspected object. An image is formed of the contents of the object based in part on the scatter signal and the relative motion signal. A detector, which may be separate or part of the scatter detector module, may exhibit sensitivity to decay products of radioactive material.

Claims

1. An inspection system for simultaneous active and passive inspection of an object by means of penetrating radiation, the system comprising:

a. an enclosed conveyance characterized by an enclosing body;

b. a source of penetrating radiation contained entirely within the body of the enclosed conveyance for generating a beam of penetrating radiation; and

c. a detector module, contained entirely within the body of the enclosed conveyance, for generating a signal based both upon penetrating radiation scattered by contents of the object and any penetrating radiation naturally emitted by the contents; and

d. a circuit switched into operation during periods of quiescence of the source of penetrating radiation for discriminating penetrating radiation naturally emitted by the contents.

2. An inspection system in accordance with claim 1, wherein the conveyance is a vehicle capable of road-travel.

3. An inspection system in accordance with claim 1, further comprising an operator console for operation by an operator disposed within the enclosed conveyance.

4. An inspection system in accordance with claim 1, further comprising an operator console for operation by a remotely disposed operator.

5. An inspection system in accordance with claim 1, wherein the conveyance is a van.

6. An inspection system in accordance with claim 1, further comprising a controller for ascertaining a specified characteristic of the contents of the object.

7. An inspection system in accordance with claim 1, further comprising a controller for converting the signal based upon detected radiation to an image.

8. An inspection system in accordance with claim 7, further comprising a monitor for displaying the image.

9. An inspection system in accordance with claim 7, further comprising an indicator coupled to the controller for providing speed information to a driver of the conveyance.

10. An inspection system in accordance with claim 1, further comprising a proximity sensor for generating a relative motion signal based on a relative disposition of the enclosed conveyance and the inspected object.

11. An inspection system in accordance with claim 1, wherein the detector module includes a scintillator material.

12. An inspection system according to claim 11, wherein the scintillator material is characterized by a high sensitivity to thermal and epi-thermal neutrons.

13. An inspection system according to claim 11, wherein the scintillator material is characterized by sensitivity to both photons and neutrons.

14. An inspection system according to claim 11, wherein the scintillator material is chosen from a group of materials exhibiting high cross-sections for interaction with thermal neutrons.

15. An inspection system for simultaneous active and passive inspection of an object by means of penetrating radiation, the system comprising:

a. an entirely enclosed conveyance characterized by an enclosing body;

b. a source of penetrating radiation contained entirely within the body of the enclosed conveyance for generating a beam of penetrating radiation of energy suited for excitation of fluorescence in specified materials;

c. a detector module, contained entirely within the body of the enclosed conveyance, for generating a signal based both upon penetrating radiation scattered by contents of the object and characteristic x-rays emitted by the contents of the object upon fluorescent excitation by the beam of penetrating radiation.

16. An inspection system in accordance with claim 15, wherein the conveyance is a vehicle capable of road-travel.

17. An inspection system in accordance with claim 15, wherein the source of penetrating radiation is an x-ray tube.

18. An inspection system in accordance with claim 15, wherein the source of penetrating radiation is an x-ray tube emitting radiation at energies below approximately 250 keV.

19. A method for inspecting an object of inspection with penetrating radiation, the method comprising:

a. generating a beam of penetrating radiation originating entirely within a body of an enclosed conveyance;

b. scanning the penetrating radiation across the object with a time-variable scanning profile;

c. detecting penetrating radiation scattered by the object into the body of the enclosed conveyance and generating a scatter signal;

d. detecting radiation naturally emitted by contents of the object of inspection and generating a naturally emitted radiation signal;

e. discriminating a signature of fissile material in the radiation naturally emitted by contents of the object; and

f. ascertaining a specified characteristic of the contents of the object based in part on the scatter signal and the naturally emitted radiation signal.