Non-invasive detection of powders concealed within diffusely scattering plastic containers

We demonstrate the potential of Spatially Offset Raman Spectroscopy (SORS) for the non-invasive detection of chemicals in powder form (e.g. illicit drugs or explosives) concealed within diffusely scattering containers. The performance of the technique is compared with that of conventional backscattering Raman spectroscopy. Enhanced sensitivity is achieved by the SORS technique's inherent ability to effectively suppress fluorescence and Raman contributions originating from the packaging. The application is demonstrated on the non-invasive detection of sugar hidden in diffusely scattering plastic bottles.