Chemical Detection in SWIR
Different chemicals absorb light differently in the SWIR spectrum. One can use these various absorption spectra to differentiate chemical types. In the example below broad band light is used to image four chemicals. All four chemical looks like clear liquid in the visible. Using broad band SWIR light one can see light is absorbed differently leading to the chemicals appearing different (darker or lighter). Using a prism or spectrometer to separate the light into individual wavelengths allows one to find the chemical fingerprint for many species in the SWIR band.
Imagery taken with 1280SciCam and Optec 25 mm F1.4 SWIR lens.