Focusless hand-held proximal Raman detection and two-dimensional mapping of explosives

Author/Creator ORCID

Date

2023-06-14

Department

Program

Citation of Original Publication

Eric R. Languirand, G. Amalthea Trobare, "Focusless hand-held proximal Raman detection and two-dimensional mapping of explosives," Proc. SPIE 12541, Chemical, Biological, Radiological, Nuclear, and Explosives (CBRNE) Sensing XXIV, 125410A (14 June 2023); https://doi.org/10.1117/12.2662856

Rights

This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.
Public Domain Mark 1.0

Subjects

Abstract

Raman sensing and mapping techniques traditionally use a tightly focused laser beam to incite and collect Raman scattered photons. A large amount of energy is typically focused in a very small (micron-sized) area potentially resulting in photo-induced damage and can be not eye-safe. In addition, when using a focused-based laser system, scanning a large area is time consuming due to the small area of interrogation and must be done at a specific distance. Therefore, either prior knowledge of the sample location (in three dimensions) is necessary, or a smaller area must be scanned. In this work, we demonstrate a hand-held proximal Raman detection instrument that uses a non-focused laser beam to interrogate a larger area. This reduces the time it takes to map a surface and provides greater flexibility in targeting the area to interrogate. Herein, we show detection and mapping of explosives in two dimensions with this hand-held proximal Raman instrument as well distance dependence of this non-focused instrument with explosive materials.