PROCEEDINGS ARTICLE | May 21, 2014
Proc. SPIE. 9101, Next-Generation Spectroscopic Technologies VII
KEYWORDS: Near infrared, Optical filters, Principal component analysis, Data modeling, Calibration, Spectroscopy, Linear filtering, Infrared spectroscopy, Absorbance, Statistical modeling
While significant progress has been made towards the miniaturization of Raman, mid-infrared (IR), and near-infrared
(NIR) spectrometers for homeland security and law enforcement applications, there remains continued interest in
pushing the technology envelope for smaller, lower cost, and easier to use analyzers. In this paper, we report on the use
of the MicroNIR Spectrometer, an ultra-compact, handheld near infrared (NIR) spectrometer, the, that weighs less than
60 grams and measures < 50mm in diameter for the classification of 140 different substances most of which are
controlled substances (such as cocaine, heroin, oxycodone, diazepam), as well as synthetic cathinones (also known as
bath salts), and synthetic cannabinoids. A library of the materials was created from a master MicroNIR spectrometer. A
set of 25 unknown samples were then identified with three other MicroNIRs showing: 1) the ability to correctly identify
the unknown with a very low rate of misidentification, and 2) the ability to use the same library with multiple
instruments. In addition, we have shown that through the use of innovative chemometric algorithms, we were able to
identify the individual compounds that make up an unknown mixture based on the spectral library of the individual
compounds only. The small size of the spectrometer is enabled through the use of high-performance linear variable filter
(LVF) technology.
