Laue, German physicist, suggested (1911) that X-rays might be diffracted from the atoms of crystal, if these were regularly arranged in a three-dimensional lattice. This was confirmed experimentally by W. Friedrich and P. Knipping (1912). If the incident X-rays form a narrow pencil beam and contain a continuous range of wavelengths, a photographic plate receiving the diffracted radiations records an array of Laue spots, the whole being a Laue diagram. For this work he was awarded a Nobel prize (1912). Laue's theory was comprehensive and somewhat elaborate. The Bragg treatment, which is much simpler, was produced soon afterwards.