Editing Dispersion relation (section)

===Electron optics===
With high-energy (e.g., {{convert|200|keV|abbr=on|disp=comma}}) electrons in a [[transmission electron microscope]], the energy dependence of higher-order [[Laue zone]] (HOLZ) lines in convergent beam [[electron diffraction]] (CBED) patterns allows one, in effect, to ''directly image'' cross-sections of a crystal's three-dimensional [[Brillouin zone|dispersion surface]].<ref>{{cite journal| author=P. M. Jones, G. M. Rackham and J. W. Steeds | year=1977|title= Higher order Laue zone effects in electron diffraction and their use in lattice parameter determination| journal=Proceedings of the Royal Society| volume=A 354
| issue=1677| page=197| doi=10.1098/rspa.1977.0064| bibcode=1977RSPSA.354..197J| s2cid=98158162}}</ref> This [[Dynamical theory of diffraction|dynamical effect]] has found application in the precise measurement of lattice parameters, beam energy, and more recently for the electronics industry: lattice strain.