Bragg's law
In many areas of science, Bragg's law – also known as Wulff–Bragg's condition or Laue–Bragg interference – is a special case of Laue diffraction that gives the angles for coherent scattering of waves from a large crystal lattice. It describes how the superposition of wave fronts scattered by lattice planes leads to a strict relation between the wavelength and scattering angle.