Pulsed laser surface fragmentation and mid-infrared laser spectroscopy for remote detection of explosives

Infrared (2–12 μm) solid-state laser sources: a review

“…The frequency span, that corresponded to 8% of the center frequency was obtained by use of a bound-to-continuum active region to yield a broad gain spectrum. A typical application of this type of DFB QCLs is in situ spectroscopic sensing, for example detection of explosives [85].…”

Long-distance in-situ methane detection using near-infrared light-induced thermo-elastic spectroscopy

“…In order to achieve safety detection, these sensors are usually designed to have the ability of long-distance gas monitoring. Optical methods are well established in many applications because they facilitate analysis without contact between human being and hazardous materials [ [2] , [3] , [4] , [5] ]. Among them, laser absorption spectroscopy for trace gas sensing are advantageous compared with other techniques, as they offer high gas specificity and sensitivity and permit real-time measurements [ [6] , [7] , [8] ].…”

Mid-Infrared Standoff Spectroscopy Using a Supercontinuum Laser with Compact Fabry–Pérot Filter Spectrometers

“…Since QCLs have extensively been used for gas phase measurements because of their narrowband single-mode emission, and a number of applications for vapor phase standoff detection were reported. 19,20 Concerning solid-state materials, photoacoustic detection using QCL illumination 21 is a suitable technique that especially works at greater standoff distances (up to 25 m). 22–24 Furthermore, Suter et al.…”

“…Since QCLs have extensively been used for gas phase measurements because of their narrowband single-mode emission, and a number of applications for vapor phase standoff detection were reported. 19,20 Concerning solid-state materials, photoacoustic detection using QCL illumination 21 is a suitable technique that especially works at greater standoff distances (up to 25 m). [22][23][24] Furthermore, Suter et al 25 reported results on diffuse reflection spectroscopy at a standoff distance of 2 m with a QCL in external cavity configuration (EC-QCL) also describing the difficulties of detecting the diffusely reflected light and its angular and morphological dependence.…”