Used with
permission of Maiken Naylor, University at Buffalo, Buffalo, NY, USA,
http://ublib.buffalo.edu/libraries/units/sel/exhibits/stamps
Max von Laue (1879-1960) postulated that diffraction of X-rays in a crystal might occur if lattice spacing and X-ray wavelength were of the same order of magnitude. Patterns such as those on the stamps were obtained experimentally, proof of the periodic structure of crystals and the wave nature of X-rays, and sufficient to win him the 1914 Nobel physics prize only two years after successful experiments.