System and methods for explosives detection using SWIR

• US 9,103,714 B2
• Filed: 10/06/2010
• Issued: 08/11/2015
• Est. Priority Date: 10/06/2009
• Status: Active Grant

• Current Assignee: Chemimage Corporation
• Original Assignee: Chemimage Corporation
• Inventors: Treado, Patrick, Nelson, Matthew, Gardner, Charles W. Jr.
• Primary Examiner(s): Geisel, Kara E
• Application Number:
  US12/924,831
• Publication Number:
  US 20110089323A1
• Time in Patent Office: 1,770 Days
• Field of Search: 356 72- 73, 250/334
• US Class Current: 1/1
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/027 Control of working procedures of a spectrometer; Failure detection; Bandwidth calculation
• CPC Class Codes: G01J 3/0278 Control or determination of height or angle information for sensors or receivers
• CPC Class Codes: G01J 3/44 Raman spectrometry; Scattering spectrometry ; Fluorescence spectrometry
• CPC Class Codes: G01N 21/359 using near infrared light
• CPC Class Codes: G01N 33/0057 Warfare agents or explosives

Abstract

A system and method for detecting explosives and explosive residues. A region of interest is surveyed using a video capture device to thereby identify a target area wherein the target area comprises an unknown material. The target area is interrogated using SWIR spectroscopic methods to form a SWIR hyperspectral image of the target area. The SWIR hyperspectral image is analyzed to thereby identify the unknown material.

Claims

1. A method comprising:

surveying a region of interest to generate a visible image;

analyzing the visible image to identify one or more targets in the region of interest, wherein the one or more targets comprise at least one unknown material;

illuminating the one or more targets to generate a plurality of interacted photons;

passing the plurality of interacted photons through a liquid crystal tunable filter selected from the group consisting of a multi-conjugate liquid crystal tunable filter, an Evans split element liquid crystal tunable filter, a Solc liquid crystal tunable filter and a Fabry Perot liquid crystal tunable filter to generate a plurality of filtered photons comprising a plurality of wavelength bands;

assessing the plurality of filtered photons using a spectroscopic imaging device to generate a SWIR hyperspectral image of the one or more targets; and

analyzing the SWIR hyperspectral image by associating the at least one unknown material with a known material.

2. The method of claim 1, wherein the SWIR hyperspectral image comprises a digital image and a spatially resolved SWIR spectrum for each pixel in the image.

3. The method of claim 1, further comprising analyzing the SWIR hyperspectral image to identify the at least one unknown material.

4. The method of claim 3, wherein the analyzing further comprises comparing the SWIR hyperspectral image to a reference data base comprising at least one SWIR reference data set associated with a known material.

5. The method of claim 4, wherein the comparing comprises applying at least one chemometric technique.

6. The method of claim 1, wherein the one or more targets are identified based on at least one of size, shape, color, and combinations thereof.

7. The method of claim 1, wherein the surveying the region of interest comprises using a visible imaging device.

8. The method of claim 7, wherein the visible imaging device comprises an RGB camera.

9. The method of claim 1, wherein the plurality of interacted photons is selected from the group consisting of photons reflected by the target area, photons absorbed by the target area, photons scattered by the target area, photons emitted by the target area and combinations thereof.

10. The method of claim 1, wherein the at least one unknown material comprises one or more of an explosive material, a non-explosive material, a chemical material, an explosive residue, a material associated with an explosive material, a disturbed earth, a command wire, and combinations thereof.

11. The method of claim 1, further comprising applying a fusion algorithm to the visible image and the SWIR hyperspectral image.

12. The method of claim 1, further comprising obtaining one or more of a MWIR hyperspectral image of the one or more targets, a LWIR hyperspectral image of the one or more targets, and combinations thereof.

13. The method of claim 12, further comprising applying a fusion algorithm to a plurality of the visible images, the SWIR hyperspectral image, the MWIR hyperspectral image, and the LWIR hyperspectral image.

14. The method of claim 1, wherein surveying further comprises employing a telescope optic configured to focus on and locate the region of interest.

15. The method of claim 1, further comprising collecting the plurality of interacted photons with a telescope optic configured to increase the magnification of the region of interest.

16. The method of claim 1, further comprising generating one or more of a dynamic visible image of the one or more targets, a dynamic hyperspectral image of the one or more targets, and combinations thereof.