SORS
Definition
Spatially offset Raman spectroscopy. The collection optics are offset from the laser spot so the detector reads photons that have travelled through the container wall and back, allowing identification of contents through opaque plastic, paper or thin walls.
- Full name
- Spatially offset Raman spectroscopy
- Mechanism
- Collection optics offset from the laser spot
- Advantage
- Reads photons that travelled through and back out of a container wall
- Application
- Identifies contents through opaque plastic, paper or thin walls
Common questions
How does SORS differ from conventional Raman spectroscopy in practice?+
Conventional Raman collects light from the same spot the laser illuminates, which is dominated by the surface layer, whereas SORS collects from points offset laterally on the surface, favouring photons that have diffused deeper through the container and back out, so the resulting spectrum is weighted toward the contents rather than the packaging.
What kinds of forensic or security screening use SORS?+
It is used to screen sealed containers such as bottles and packages for concealed or unknown chemicals, including suspected drugs or hazardous substances, without opening the packaging, which is valuable at scenes or checkpoints where opening a container is unsafe or would compromise evidence.
Related terms
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- SERS
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