System and method for X-ray diffraction imaging

• US 7,835,495 B2
• Filed: 10/31/2008
• Issued: 11/16/2010
• Est. Priority Date: 10/31/2008
• Status: Active Grant

• Current Assignee: Morpho Detection LLC (Smiths Group International Holdings Ltd.)
• Original Assignee: Morpho Detection (Safran SA)
• Inventors: Harding, Geoffrey
• Primary Examiner(s): Glick; Edward J
• Assistant Examiner(s): Artman; Thomas R
• Application Number:
  US12/263,023
• Publication Number:
  US 20100111255A1
• Time in Patent Office: 746 Days
• Field of Search: 378/6, 378/57, 378/71, 378/73, 378 86- 90
• US Class Current: 378/87
• CPC Class Codes: G01N 23/20083 by using a combination of at least two measurements at least one being a transmission measurement and one a scatter measurement
• CPC Class Codes: G01T 1/00 Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation G01T3/00, G01T5/00 take precedence
• CPC Class Codes: G01V 5/22 Active interrogation, i.e. by irradiating objects or goods using external radiation sources, e.g. using gamma rays or cosmic rays
• CPC Class Codes: G01V 5/222 measuring scattered radiation

Abstract

An X-ray diffraction imaging system is provided. The X-ray diffraction imaging system includes an X-ray source configured to emit an X-ray pencil beam and a scatter detector configured to receive scattered radiation having a scatter angle from the X-ray pencil beam. The scatter detector is located substantially in a plane and includes a plurality of detector strips. A first detector strip has a first width equal to a linear extent of the X-ray pencil beam measured at the plane in a direction parallel to the first width.

Claims

1. An X-ray diffraction imaging system, comprising:

an X-ray source configured to emit an X-ray fan beam and a set of X-ray pencil beams;

an examination area;

a plurality of scatter detectors, each of said plurality of scatter detectors configured to receive scattered radiation from an interaction of an X-ray pencil beam of the set of X-ray pencil beams and a container in said examination area, the scattered radiation having a scatter angle, wherein at least one of said plurality of scatter detectors is located substantially in a plane, said at least one scatter detector comprises a plurality of detector strips, a first detector strip of said plurality of detector strips having a first width equal to a width of the X-ray pencil beam measured where the X-ray pencil beam crosses the plane;

a transmission detector array configured to receive the X-ray fan beam attenuated by the container; and

a data processing system configured to combine an output from said transmission detector array and an output from said plurality of scatter detectors to generate information regarding the container.

2. An X-ray diffraction imaging system in accordance with claim 1, wherein:

the scattered radiation comprises a plurality of portions of scattered radiation;

said first detector strip is configured to receive a first portion of the plurality of portions of scattered radiation, the first portion originating from a first distance, measured perpendicular to the plane, from the plane; and

a second detector strip of said plurality of detector strips is configured to receive a second portion of the plurality of portions of scattered radiation, the second portion originating from a second distance, measured perpendicular to the plane, from the plane, and said second detector strip has a second width b defined by;

3. An X-ray diffraction imaging system in accordance with claim 1, wherein:

the scattered radiation comprises a plurality of portions of scattered radiation;

said first detector strip is configured to receive a first portion of the plurality of portions of scattered radiation, the first portion originating from a first distance, measured perpendicular to the plane, from the plane; and

at least one of said plurality of detector strips comprises a height Z_D defined by;

4. An X-ray diffraction imaging system in accordance with claim 1, wherein said X-ray source is configured to emit the set of X-ray pencil beams substantially in a first plane and the X-ray fan beam substantially in a second plane.

5. An X-ray diffraction imaging system in accordance with claim 1, wherein said data processing system is further configured to perform an X-ray diffraction analysis using the output from said plurality of scatter detectors, and the information regarding the container comprises one of a multiview projection and a section image of the container, the one of a multiview projection and a section image identifies a location in the container of a material detected by the X-ray diffraction analysis.

6. An X-ray diffraction imaging system in accordance with claim 1, wherein said X-ray source comprises a plurality of focus points, each of said plurality of focus points is configured to emit the X-ray fan beam and the set of X-ray pencil beams.

7. An X-ray diffraction imaging system in accordance with claim 6, wherein said plurality of focus points are located substantially along an axis of said X-ray source, said X-ray source is configured to generate the X-ray fan beam and the set of X-ray pencil beams from each focus point of said plurality of focus points in sequence along the axis.

8. A method of operating an X-ray diffraction imaging system, said method comprising:

receiving at a plurality of scatter detectors a portion of scattered radiation from a container, the scattered radiation having a scatter angle, wherein at least one of the plurality of scatter detectors is located substantially in a plane, the at least one scatter detector comprises a plurality of detector strips, and a first width of a first detector strip of the plurality of detector strips is equal to a width of an X-ray pencil beam measured where the X-ray pencil beam crosses the plane;

receiving an X-ray fan beam attenuated by the container at a transmission detector array; and

generating information regarding the contents of the container by combining an output from the transmission detector array and an output from the plurality of scatter detectors.

9. A method in accordance with claim 8, wherein the portion of the scattered radiation comprises a plurality of portions of scattered radiation, said receiving at a plurality of scatter detectors a portion of scattered radiation further comprises:

receiving a first portion of the plurality of portions of scattered radiation at the first detector strip of the plurality of detector strips, the first portion originating from a first distance, measured perpendicular to the plane, from the plane; and

receiving a second portion of the plurality of portions of scattered radiation at a second detector strip of the plurality of detector strips, the second portion originating from a second distance, measured perpendicular to the plane, from the plane, wherein a second width b of the second detector strip is defined by;

10. A method in accordance with claim 8, wherein the portion of the scattered radiation comprises a plurality of portions of scattered radiation, said receiving at a plurality of scatter detectors a portion of scattered radiation further comprises receiving a first portion of the plurality of portions of scattered radiation at the first detector strip of the plurality of detector strips, the first portion originating from a first distance, measured perpendicular to the plane, from the plane, wherein a height Z_D of at least one of the plurality of detector strips is defined by:

11. A method in accordance with claim 8, wherein the scattered radiation arises from a set of X-ray pencil beams directed at the container, the set of X-ray pencil beams lies substantially in a first plane, said method further comprises orienting the X-ray fan beam substantially in a second plane.

12. A method in accordance with claim 8, wherein said generating information regarding the contents of the container further comprises:

performing an X-ray diffraction analysis using the output from the plurality of scatter detectors; and

generating one of a multiview projection and a section image of the container, the one of a multiview projection and a section image identifies a location in the container of a material detected by the X-ray diffraction analysis.

13. A method in accordance with claim 8, wherein the scattered radiation arises from a set of X-ray pencil beams directed at the container, said method further comprises transmitting the X-ray fan beam and the set of X-ray pencil beams from each of a plurality of focus points of an X-ray source.

14. A method in accordance with claim 13, wherein the plurality of focus points are located substantially along an axis of the X-ray source, said transmitting the X-ray fan beam and the set of X-ray pencil beams from each of the plurality of focus points further comprises generating the X-ray fan beam and the set of X-ray pencil beams from each focus point of the plurality of focus points in sequence along the axis.

15. An X-ray scatter detection system, comprising:

an X-ray source configured to emit an X-ray pencil beam; and

a scatter detector configured to receive scattered radiation having a scatter angle from the X-ray pencil beam, said scatter detector located substantially in a plane, said scatter detector comprising a plurality of detector strips, a first detector strip of said plurality of detector strips having a first width equal to a width of the X-ray pencil beam measured where the X-ray pencil beam crosses the plane.

16. An X-ray scatter detection system in accordance with claim 15, wherein:

the scattered radiation comprises a plurality of portions of scattered radiation;

said first detector strip is configured to receive a first portion of the plurality of portions of scattered radiation, the first portion originating from a first distance, measured perpendicular to the plane, from the plane; and

a second detector strip of said plurality of detector strips is configured to receive a second portion of the plurality of portions of scattered radiation, the second portion originating from a second distance, measured perpendicular to the plane, from the plane, said second detector strip comprises a second width b defined by;

17. An X-ray scatter detection system in accordance with claim 15, wherein:

the scattered radiation comprises a plurality of portions of scattered radiation;

said first detector strip is configured to receive a first portion of the plurality of portions of scattered radiation, the first portion originating from a first distance, measured perpendicular to the plane, from the plane; and

at least one of said plurality of detector strips comprises a height Z_D defined by;

18. An X-ray scatter detection system in accordance with claim 15, further comprising a primary collimator, wherein the width of the X-ray pencil beam measured at the plane is determined by a channel width of the primary collimator.