Combined scatter and transmission multi-view imaging system
View Patent ↗The present specification discloses a multi-view X-ray inspection system having, in one of several embodiments, a three-view configuration with three X-ray sources. Each X-ray source rotates and is configured to emit a rotating X-ray pencil beam and at least two detector arrays, where each detector array has multiple non-pixellated detectors such that at least a portion of the non-pixellated detectors are oriented toward both the two X-ray sources.
1. An X-ray inspection system for scanning an object, the inspection system comprising:
a first X-ray source and a second X-ray source, each configured to simultaneously emit rotating X-ray beams for irradiating the object, wherein each of said X-ray beams defines a transmission path;
a detector array comprising at least one transmission detector placed between at least two backscatter detectors, wherein each of said backscatter detectors detects backscattered X-rays emitted by the first X-ray source placed on a first side of the object and wherein the transmission detectors detects transmitted X-rays emitted by the second X-ray source placed on an opposing side of the object; and
at least one controller for controlling each of the first and second X-ray sources to concurrently scan the object in a coordinated, non-overlapping, manner such that the transmission paths of each of said X-ray beams does not cross.
2. The X-ray inspection system as claimed in claim 1 wherein the detector array comprises at least two rectangular profile backscatter detectors and a square profile transmission detector positioned between said at least two rectangular profile backscatter detectors.
3. The X-ray inspection system as claimed in claim 1 wherein the detector array comprises a transmission detector positioned between two backscatter detectors and wherein the detectors are placed within a single plane facing the object begin scanned and the transmission detector has a smaller exposed surface area than each of the backscatter detectors.
4. The X-ray inspection system as claimed in claim 1 further comprising a pair of fixed collimators positioned between the transmission detector and one of said at least two backscatter detectors.
5. The X-ray inspection system as claimed in claim 1 wherein each of the X-ray sources comprises an extended anode X-ray tube, a rotating collimator assembly, a bearing, a drive motor, and a rotary encoder.
6. The X-ray inspection system as claimed in claim 1 wherein each of the first and second X-ray sources comprises:
an extended anode X-ray tube coupled with a cooling circuit, the anode being at ground potential;
a rotating collimator assembly comprising at least one collimating ring with slots cut at predefined angles around a circumference of the collimator, a length of each slot being greater than a width and an axis of rotation of the slot, and the width of the slots defining an intrinsic spatial resolution of the X-ray inspection system in a direction of the scanning;
a bearing for supporting a weight of the collimator assembly and transferring a drive shaft from the collimator assembly to a drive motor;
a rotary encoder for determining an absolute angle of rotation of the X-ray beams; and
a secondary collimator set for improving spatial resolution in a perpendicular scanning direction.
7. The X-ray inspection system as claimed in claim 6 wherein the controller receives speed data comprising a speed of the object and, based upon said speed data, adjusts at least one of a collimator rotation speed of an X-ray source, a data acquisition rate, or an X-ray tube current based upon said speed data.