Each Wednesday we feature a specific wavelength of light and user submitted applications. This week's wavelength will focus on using a handheld 532 nm laser for Raman spectroscopy for drug detection.
This is a classic Raman setup. The picture below is a new handheld version!
Description of Laser Application
Raman spectroscopy is a spectroscopic technique based on inelastic scattering of monochromatic light from a laser source. Inelastic scattering means that the frequency of photons in monochromatic light changes upon interaction with a sample.
In their own words:
"Most handheld Raman-based chemical detection systems in use today utilize a 532nm or 785nm laser to excite the sample, which are known to generate heavy sample fluorescence interference. This makes analysis of colored materials extremely challenging. For this reason, the use of handheld Raman based detection systems has historically been used primarily for identifying white powders and clear liquids, which are the least likely samples to produce fluorescence when excited with a lower excitation laser. "