Method of electron beam transport in an X-ray scanner

Patent metadata

Field	Value
Publication number	US-9442213-B2
Application number	US-201414270874-A
Country	US
Kind code	B2
Filing date	May 6, 2014
Priority date	Jan 19, 2010
Publication date	Sep 13, 2016
Grant date	Sep 13, 2016

Abstract

The present invention provides a multi-view X-ray inspection system. In one embodiment, a beam steering mechanism directs the electron beam from an X-ray source to multiple production targets which generate X-rays for scanning which are subsequently detected by a plurality of detectors to produce multiple image slices (views). The system is adapted for use in CT systems. In one embodiment of a CT system, an electron beam generated by a single radiation source is steered by an electron beam transport mechanism comprising at least two dipoles and a quadrupole on to a target arranged in an approximated arc. The inspection system, in any configuration, can be deployed inside a vehicle for use as a mobile detection system.

First claim

We claim:

1. An inspection system for generating a plurality of scanning views of an object under inspection, comprising:
a source for generating at least one high-energy electron beam;
a first set of magnets for directing the at least one electron beams into an electron beam transport system;
the electron beam transport system comprising at least two electron beam transport stations, for directing said at least one electron beam to more than one target, wherein said more than one target produces radiation beams for scanning the object;
at least one second set of magnets to maintain the at least one electron beam in a desired trajectory;
at least one detector array for detecting said radiation and generating said plurality of scanning views;
a transport mechanism to move the object through the system; and
a processor for reconstructing tomographic images by combining said plurality of scanning views.

2. The inspection system of claim 1 , wherein the source is a linac.

3. The inspection system of claim 1 , wherein two high energy electron beams are generated in an interlaced mode, wherein the energy of a first energy electron beam is lower than the energy of a second electron beam.

4. The inspection system of claim 1 wherein the electron source is pulsed with a pulsing frequency is 500 Hz.

5. The inspection system of claim 1 , wherein the first set of magnets is used in combination with slits to filter out low energy electron components.

6. The inspection system of claim 3 , wherein the first set of magnets comprises two magnets for turning the interlaced beams at different angles such that they end up on the same trajectory.

7. The inspection system of claim 1 wherein each of said at least two electron beam transport stations comprises, each station comprising:
a first pulsed magnet to extract electrons from the beam and a second pulsed magnet for bringing electrons having different energies from the first magnet onto a same path, wherein a sum of the angles of the magnets is approximately 270 degrees and wherein the first pulsed magnet is roughly 90 degrees and the second pulsed magnet is roughly 180 degrees; and
two quadrupoles to focus the beam on one of said more than one target in both directions to achieved a desired focal-spot size.

8. The inspection system of claim 7 , wherein the electron transport station comprises a steering magnet for steering an electron beam into multiple positions on one of said more than one target.

9. The inspection system of claim 1 , wherein the second set of magnets comprise an achromat that includes two dipoles and one quadrupole.

10. The inspection system of claim 3 wherein the processor for reconstructing tomographic images uses data generated from the two interlaced high energy electron beams to create tomographic images to obtain atomic number information.

11. An inspection system for generating a plurality of scanning views of an object under inspection, comprising:
a source for generating a high-energy electron beam;
a first magnet for directing the high energy electron beam into an electron beam transport system to a corresponding at least one production target for generating radiation beams for scanning the object;
said electron beam transport system comprising at least two electron beam transport stations, wherein each of said at least two electron beam transport stations comprises
a first dipole magnet to extract electrons from the high-energy beam and a second dipole magnet for bringing electrons having different energies from the first magnet onto the same trajectory, wherein a sum of the angles of the magnets is approximately 90 degrees and wherein the first dipole magnet is roughly 45 degrees and the second dipole magnet is roughly 45 degrees;
a quadrupole magnet placed symmetrically between the first and second dipole magnets; and
two quadrupoles to focus the high-energy beam on the target in orthogonal directions to achieved a desired focal-spot size; and

at least one detector array for detecting said radiation beams to produce said plurality of scanning views;
a transport mechanism to move the object through the system; and
a processor for reconstructing tomographic images by combining said plurality of scanning views.

12. The inspection system of claim 11 wherein said at least one production target is at least one of an extended target or a separate target for each electron beam transport station.

13. The inspection system of claim 11 wherein a second high energy radiation beam is generated after a first scan process by changing magnetic parameters of the system to transport a second high energy beam having a different energy than the first high energy beam.

14. The inspection system of claim 13 wherein the object is scanned at the first energy and then rescanned at the second energy and wherein data generated from both scans is combined to obtain atomic number information.

15. The inspection system of claim 11 , wherein the first magnet is used in combination with slits to filter out low energy electron components.

16. An inspection system for generating a plurality of scanning views of an object under inspection, comprising:
a source for generating at least one beam of charged particles;
a beam steering system comprising at least two electron beam transport stations, each of said stations directing said charged particles to a plurality of locations along at least one target, said at least one target generating a plurality of neutron beams for scanning the object;
at least one neutron detector array for detecting said neutron beams and generating said plurality of scanning views;
a transport mechanism to move the object through the system; and
a processor for reconstructing tomographic images by combining said plurality of scanning views obtained from the at least one neutron detector array.

17. The system of claim 16 wherein said particle is a low-energy deuteron (300 kV or lower).

18. The system of claim 17 the at least one target is tritium-based.

19. The system of claim 16 wherein said particle is high-energy deuteron (at least 3 MV).

20. The system of claim 19 wherein said at least one target is deuterium- or beryllium-based.

21. The system of claim 16 wherein said particle is a proton.

22. The system of claim 21 wherein said at least one target is lithium.

23. The system of claim 16 wherein the at least one target is positioned along an arcuate path.

Assignees

• Rapiscan Systems Inc

Inventors

• Bendahan Joseph
• Jones James Kevin
• Angal-Kalinin Deepa
• Marinov Kiril Borisov

Classifications

• G01T3/00

  Measuring neutron radiation (G01T5/00 takes precedence) · CPC title

• G01V5/005 Primary

  Physics · mapped topic

• G01V5/226 Primary

  using tomography · CPC title