22 May 2015 Ozone alteration for background references using QCL-based mid infrared standoff spectroscopy
Author Affiliations +
Abstract
Mid-Infrared standoff spectroscopy using Quantum Cascade Lasers has been a focus of on-going research for many years. When attempting to detect trace analyte residues, the greatest challenge facing this technology is not in the lasers, but the difficulty in creating a spectroscopic background reference for an unknown surface. Such techniques as Differential Location Measurements fail when analyte concentrations are below 1 μg/cm2. To overcome this challenge of unknown surface backgrounds, we propose a technique to alter the IR absorption peaks of a target analyte by exposing the surface to a high intensity, alternating electric field in a standoff fashion. The high intensity electric field generates ozone radicals from the local air, oxidizing organic compounds on the surface. A spectrum of the surface before and after the ozone radicals is obtained. The ozone altered spectrum acts as the reference background and is compared against the un-altered spectrum, generating a differential signal used to identify the target analyte.
© (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Inseok Chae, Inseok Chae, C. W. Van Neste, C. W. Van Neste, Thomas Thundat, Thomas Thundat, "Ozone alteration for background references using QCL-based mid infrared standoff spectroscopy", Proc. SPIE 9467, Micro- and Nanotechnology Sensors, Systems, and Applications VII, 94672P (22 May 2015); doi: 10.1117/12.2178606; https://doi.org/10.1117/12.2178606
PROCEEDINGS
5 PAGES


SHARE
RELATED CONTENT


Back to Top