XinRay

Machines that scan luggage at airports and look inside the body still bear the imprint of Wilhelm Roentgen, the German physics professor who stumbled upon X-rays 114 years ago.

That's because little has changed in the way X-rays are generated: Today's most sophisticated CT scanners produce detailed, three-dimensional images of the heart or the brain with the help of vaccuum tubes that are technologically similar to the one Roentgen used for the iconic image of his wife's hand with rings.