Handheld scanners called Raman scanners, weighing just one-third of a kilo, are being used by US narcotics squads and airports to detect drugs.
The scanners work by detecting the molecular structure of the object they are scanning. If you shoot a beam of light on an object, a very small part of it interacts with the atoms of the object and scatters light in a pattern or spectrum unique to that particular molecule.This is the Raman Effect. It is difficult to detect, and typically needs lasers to amplify the signal. Every molecule has a different Raman pattern. This is why Raman scanning has been called the fingerprinting of the universe: it can identify substances as surely as fingerprints can identify humans.
Scanners have a laser, spectroscope and an electronic heart that can recognize Raman patterns. This yields almost instant recognition of target substances.
Scientists aim ultimately to create a database of Raman patterns of every substance for easy identification.
The Atlantic reports other mash-ups of the Raman Effect -
The potential medical applications of Raman technology are perhaps the most exciting. Researchers at Stanford University are experimenting with it as a non-invasive tool to diagnose breast, lung, and other cancers. River Diagnostics, in Rotterdam, is marketing a bacteria-strain analyzer to identify pathogens in real time and combat hospital-acquired infections. Diabetics may someday be able to monitor their glucose without poking themselves to get a drop of blood. Allergy sufferers may be able to instantly detect which pesky pollens are in the air and respond accordingly.
I found it interesting that I read this article by my favorite Indian columnist who probably first read it in an American magazine that carried this feature about an Indian scientist's path-breaking discovery that is finding application outside India scores of years after he first observed it. Goes to show how geographies are irrelevant for ideas & why good ideas should keep flowing.
The funny cover of The Atlantic that features the Raman article
Also see:
Accidental Discoveries
Geniuses
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