System and method for X-ray diffraction imaging
View Patent ↗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.
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:
b
=
b
m
L
2
L
2
m
wherein b m is the first width, L 2m is the first distance, and L 2 is the second distance.
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:
Z
D
=
b
m
2
8
L
2
m
tan
(
θ
)
wherein b m is the first width, L 2m is the first distance, and θ is the scatter angle.
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:
b
=
b
m
L
2
L
2
m
wherein b m is the first width, L 2m is the first distance, and L 2 is the second distance.
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:
Z
D
=
b
m
2
8
L
2
m
tan
(
θ
)
wherein b m is the first width, L 2m is the first distance, and θ is the scatter angle.
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:
b
=
b
m
L
2
L
2
m
wherein b m is the first width, L 2m is the first distance, and L 2 is the second distance.
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:
Z
D
=
b
m
2
8
L
2
m
tan
(
θ
)
wherein b m is the first width, L 2m is the first distance, and θ is the scatter angle.
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.