X-rays were soon reproduced in laboratories
around the world. They were found to have a medical use,
because the penetrating radiation could guide a surgeon before
surgery began. X-rays could show damaged bones, or locate
a bullet beneath the patient's skin.
For
his discovery, Röntgen was awarded the very first
Nobel Prize in Physics in 1901. At the presentation
speech it was noted that much success would be gained
in physics "when this strange energy form is sufficiently
investigated and its wide field thoroughly explored".
The first question was whether the X-rays behaved as
waves or particles.
One
physicist who studied the rays was Max von Laue in Germany.
Laue believed that X-rays were similar to light waves
and not some form of tiny particle. In 1905 Charles
Barkla in Edinburgh had shown that X-rays could be polarised,
but the rays could not be made to refract. If they were
waves, they must have a very short wavelength.
Von
Laue's colleague, Wilhelm Wien, calculated that the
wavelength should be around one hundredth of a nanometre,
ten thousand times shorter than the wavelength of visible
light. Von Laue had been studying the diffraction of
light using narrow slits and wondered if X-rays could
also be diffracted if the slits were small enough.
