Are transducers, like an RFID tag, visible on X-rays?
First off, an RFID tag is not a transducer. A transducer is a device that converts one type of energy or signal to another form of energy or signal—for example, a microphone takes acoustic signal and converts it to digital signals. RFID does not do that. An RFID tag receives RF signals and responds with RF signals. It is, therefore, a transponder. And yes, it is visible on an X-ray, because the antenna is composed of metal, through which X-rays do not pass. A transponder would be easy to spot on an X-ray film, just as bone screws or bullet fragments would be.
—Mark Roberti, Founder and Editor, RFID Journal
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