Louise Levathes reports on the proliferation of small, inexpensive scanners to uncover what lies within:

Raman devices work by shooting a laser beam at an object. The laser light interacts with the object’s electrons, making the atoms vibrate and shifting the energy of the laser photons up or down. The shift creates a visual patternthe Raman effect, named after C. V. Raman, the Indian scientist who discovered it in the 1920s. Almost every material has its own unique Raman pattern, based on how strongly its atoms are bonded.

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.

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