from Technology Review -
Terahertz Transistor Could Usher in Era of Cheap Surveillance Video Cameras
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An update on development in an imaging technique that had been found to be useful in the technical examination of historic cultural artefacts. Beside being able to reveal hidden features (much like x-rays), the detected signals could also potentially indicate the type of material being examined.

See earlier post on tetrahertz (or T-ray) imaging here.
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