A condition which (1) is defined as twice the lattice spacing in a large crystal multiplied with the sine of the Bragg angle between the incident beam and a set of lattice planes, being a whole multiple of the radiation wavelength, and (2) if satisfied, may allow to relate the location of a scattering intensity maximum within a diffraction pattern to the corresponding lattice plane spacing.

Bragg's law is commonly used in TEM to calculate the lattice spacing of a crystal from a diffraction pattern, most commonly zone axis or ring diffraction patterns.While Bragg's Law applies to real space (or direct space), Laue condition is its equivalent in reciprocal space (or k-space).We define the use of Bragg's Law for extracting information about lattice plane spacing as \"may allow to\" because in addition to Bragg's law also other conditions need to be satisfied. For example the structure factor must be non-zero.Bragg's Law is a condition for constructive interference of diffracted radiation.