X-ray scanner with partial energy discriminating detector array

• US 10,353,109 B2
• Filed: 10/19/2017
• Issued: 07/16/2019
• Est. Priority Date: 01/07/2013
• Status: Active Grant

• Current Assignee: Rapiscan Systems Incorporated (OSI Systems Incorporated)
• Original Assignee: Rapiscan Systems Incorporated (OSI Systems Incorporated)
• Inventors: Hanley, Gerard Andrew
• Primary Examiner(s): Ippolito, Nicole M
• Application Number:
  US15/787,886
• Publication Number:
  US 20180292565A1
• Time in Patent Office: 635 Days
• Field of Search: 378 11, 378 14, 378145, 378 57, 378 62
• CPC Class Codes: G01V 5/224 Multiple energy techniques using one type of radiation, e.g. X-rays of different energies

Abstract

The present specification describes a scanning/inspection system configured as a dual-view system using dual-energy sensitive stacked detectors that are partially populated with multi-energy discriminating detectors for overall enhanced energy resolution and therefore improved discrimination of materials through better estimation of material physical properties such as density and effective atomic number.

Claims

1. A system for screening an object, comprising:

a conveyor to move the object through an inspection region;

a first X-ray source configured to transmit X rays through the object for generating a vertical X-ray projection view of the object;

a second X-ray source configured to transmit for X rays through the object for generating a horizontal X-ray projection view of the object, wherein the vertical X-ray projection view and horizontal X-ray projection view spatially overlap and define the inspection region;

a first array of detectors, wherein the first array of detectors comprises a first set of dual-energy sensitive detectors and a first set of energy discriminating detectors positioned adjacent, not behind, each other relative to the first X-ray source; and

a second array of detectors, wherein the second array of detectors comprises a second set of dual-energy sensitive detectors and a second set of energy discriminating detectors positioned adjacent, not behind, each other relative to the first X-ray source and wherein the second array of detectors are positioned substantially perpendicular to the first array of detectors within the inspection region.

2. The system of claim 1 further comprising a receptacle configured to carry the object on the conveyor, wherein the receptacle is a tray further comprising a foam insert that has at least one channel to align the object for screening.

3. The system of claim 1 wherein the first set of dual-energy sensitive detectors comprise stacked detectors.

4. The system of claim 1 wherein the first set of energy discriminating detectors and second set of energy discriminating detectors are fabricated from high-Z semiconductor materials including at least one of cadmium-telluride (CdTe), cadmium-zinc-telluride (CZT), mercury iodide (HgI.sub.2), selenium (Se), lead iodide (PbI.sub.2), or gallium arsenide (GaAs).

5. The system of claim 1 wherein the object is a liquid, aerosol, gel (LAG) item.

6. The system of claim 1 further comprising a processor for receiving output signals from each of the first array of detectors and the second array of detectors and overlaying said output signals onto a visual image of the object.

7. A method for screening an objects, comprising:

moving the object through an inspection region using a conveyor;

generating a vertical X-ray projection view of the object using a first X-ray source;

generating a horizontal X-ray projection view of the object using a second X-ray source, wherein the vertical X-ray projection view and horizontal X-ray projection view spatially overlap and define the inspection region;

detecting X-rays transmitted through the said object using a first array of detectors and a second array of detectors, wherein the first array of detectors comprises a first set of dual-energy sensitive detectors and a first set of energy discriminating detectors positioned adjacent, not behind, each other relative to the first X-ray source and wherein the second array of detectors comprises a second set of dual-energy sensitive detectors and a second set of energy discriminating detectors positioned adjacent, not behind, each other relative to the first X-ray source and wherein the second array of detectors are positioned substantially perpendicular to the first array of detectors within the inspection region.

8. The method of claim 7 further comprising a receptacle wherein the receptacle is a tray further comprising a foam insert that has at least one channel to align the object for screening.

9. The method of claim 7 wherein the first set of dual energy sensitive detectors and the second set of dual energy sensitive detectors comprise stacked detectors.

10. The method of claim 7 wherein the first set and second set of energy discriminating detectors comprise at least one of high-Z semiconductor materials, cadmium-telluride (CdTe), cadmium-zinc-telluride (CZT), mercury iodide (HgI.sub.2), selenium (Se), lead iodide (PbI.sub.2), or gallium arsenide (GaAs).

11. The method of claim 7 wherein the object is a liquid, aerosol, gel (LAG) item.

12. The method of claim 7 further comprising processing output signals from the first array of detectors and the second array of detectors to form a visual image of the object.