Apparatus and method for rapid detection of explosives residue from the deflagration signature thereof

• US 5,638,166 A
• Filed: 05/18/1995
• Issued: 06/10/1997
• Est. Priority Date: 05/18/1995
• Status: Expired due to Fees

• Current Assignee: Los Alamos National Security LLC (Government of the United States of America)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Funsten, Herbert O., McComas, David J.
• Primary Examiner(s): Epps, Georgia Y.
• Assistant Examiner(s): VIERRA EISENBERG, JASON D
• Application Number:
  US08/444,976
• Time in Patent Office: 754 Days
• Field of Search: 356/36, 356/311-312, 356/315, 250/554
• US Class Current: 356/36
• CPC Class Codes: G01N 1/2208 with impactors
• CPC Class Codes: G01N 1/4022 by thermal techniques; Phase changes
• CPC Class Codes: G01N 2001/007 Devices specially adapted for forensic samples, e.g. tamper-proofing, sample tracking
• CPC Class Codes: G01N 2001/022 sampling for security purposes, e.g. contraband, warfare agents
• CPC Class Codes: G01N 2001/028 Sampling from a surface, swabbing, vaporising

Abstract

Apparatus and method for rapid detection of explosives residue from the deflagration signature thereof. A property inherent to most explosives is their stickiness, resulting in a strong tendency of explosive particulate to contaminate the environment of a bulk explosive. An apparatus for collection of residue particulate, burning the collected particulate, and measurement of the optical emission produced thereby is described. The present invention can be utilized for real-time screening of personnel, cars, packages, suspected devices, etc., and provides an inexpensive, portable, and noninvasive means for detecting explosives.

Claims

1. An apparatus for determining the presence of particulate from explosive materials, which comprises in combination:

a light-tight enclosure;

a heated surface located within said light-tight enclosure for receiving the particulate and maintained above the deflagration temperature of the particulate, wherein an optical signature is emitted from the deflagration of particulate thereon; and

photodetector means located within said light-tight enclosure and disposed such that the emitted optical signature is detected.

2. The apparatus for determining the presence of particulate from explosive materials as described in claim 1, further comprising means for collecting the particulate.

3. The apparatus for determining the presence of particulate from explosive materials as described in claim 2, wherein said means for collecting the particulate comprises means for entraining the particulate in a stream of air, and means for directing the stream of air containing the particulate over said heated surface such that a portion of the particulate impinge thereon.

4. The apparatus for determining the presence of particulate from explosive materials as described in claim 3, wherein said means for entraining the particulate to be investigated in a stream of air, and said means for directing the stream of air containing the particulate over said surface comprise a vacuum pump for evacuating said light-tight enclosure, and tubing means having a first open end located in the vicinity of the particulate to be sampled and a second open end attached to the light-tight enclosure in the vicinity of said heated surface.

5. A method for determining the presence of particulate from explosive materials, which comprises the steps of:

depositing particulate on a surface heated to above the deflagration temperature of the particulate and located within a light-tight enclosure, wherein an optical signature is emitted from the deflagration of the particulate; and

detecting the emitted optical signature.

6. An apparatus for determining the presence of particulate from explosive materials, which comprises in combination:

a light-tight enclosure;

means located within said light-tight enclosure for heating the particulate to above the deflagration temperature thereof without direct excitation from flames or plasmas, wherein an optical signature is emitted from the deflagration of the particulate; and

photodetector means located within said light-tight enclosure disposed such that the emitted optical signature is detected.

7. A method for determining the presence of particulate from explosive materials, which comprises the steps of:

heating the particulate to above the deflagration temperature thereof without direct excitation from flames or plasmas, within a light-tight enclosure, wherein an optical signature is emitted from the deflagration of the particulate; and

detecting the emitted optical signature.