Raman spectrometry is becoming a common method for identification of hazardous compounds and illicit drugs. Historically, infrared absorption spectroscopy was the common method, but the mainstream has gradually shifted to Raman spectroscopy. In particular, Raman spectrometry has a couple of advantages over infrared spectrometry for onsite rapid analysis. First, handheld Raman spectrometers can analyze contents through transparent or translucent containers, which infrared absorption spectrometers cannot. Second, Raman spectrometer can analyze wet samples, but infrared absorption spectrometer cannot.
In the past, handheld Raman spectrometers had issues with overlap of fluorescence, depending on sample type. The reason behind this was that the wavelength of excitation laser was mostly 785 nm. The novel handheld Raman spectrometers for hazardous materials and drugs with 1064 nm excitation laser described in this article can reduce the overlap of fluorescence drastically. Other advantages of the novel handheld Raman spectrometers are described in the later sections.