Enabling standoff detection of hazardous materials using a fiber optic coupled quantum cascade infrared laser system

Insertion loss is an important parameter used to characterize passive fiber-optic components, such as WDM couplers and variable optical attenuators. This article describes an automated insertion loss measurement system which incorporates 980 nm, 1310 nm, 1529 nm and 1561 nm DFB lasers and two internal fiber optic standards. Insertion loss measurements collected with the system for WDM couplers and internal standards are presented. The system repeatability was validated by measuring the insertion loss for a WDM coupler six times at 980 nm, 1310 nm, 1529 nm and 1561 nm over 3 days period. The standard deviation calculated for the insertion loss measurements is less than 0.11 dB and the %CV is less than 1%.

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Standoff detection of chemical plumes from high explosive open detonations using a swept-wavelength external cavity quantum cascade laser

Journal of Applied Physics ◽

10.1063/5.0023228 ◽

2020 ◽

Vol 128 (16) ◽

pp. 163103

Author(s):

Mark C. Phillips ◽

Sivanandan S. Harilal ◽

Jeremy Yeak ◽

R. Jason Jones ◽

Sonia Wharton ◽

...

Keyword(s):

Quantum Cascade Laser ◽

High Explosive ◽

External Cavity ◽

Quantum Cascade ◽

Standoff Detection

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Fiber Optic Coupled Raman Based Detection of Hazardous Liquids Concealed in Commercial Products

International Journal of Spectroscopy ◽

10.1155/2012/463731 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 4

Author(s):

Michael L. Ramírez-Cedeño ◽

Natalie Gaensbauer ◽

Hilsamar Félix-Rivera ◽

William Ortiz-Rivera ◽

Leonardo Pacheco-Londoño ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Raman Spectroscopy ◽

Fiber Optic ◽

Hazardous Materials ◽

Chemical Warfare Agent ◽

Chemical Warfare ◽

Consumer Products ◽

Algorithm Analysis ◽

Triethyl Phosphate ◽

Industrial Compounds

Raman spectroscopy has been widely proposed as a technique to nondestructively and noninvasively interrogate the contents of glass and plastic bottles. In this work, Raman spectroscopy is used in a concealed threat scenario where hazardous liquids have been intentionally mixed with common consumer products to mask its appearance or spectra. The hazardous liquids under consideration included the chemical warfare agent (CWA) simulant triethyl phosphate (TEP), hydrogen peroxide, and acetone as representative of toxic industrial compounds (TICs). Fiber optic coupled Raman spectroscopy (FOCRS) and partial least squares (PLS) algorithm analysis were used to quantify hydrogen peroxide in whiskey, acetone in perfume, and TEP in colored beverages. Spectral data was used to evaluate if the hazardous liquids can be successfully concealed in consumer products. Results demonstrated that FOC-RS systems were able to discriminate between nonhazardous consumer products and mixtures with hazardous materials at concentrations lower than 5%.

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