Sources of Error in Accurate Orientations Determined by Electron Diffraction

Factors limiting the accuracy of orientations determined by electron diffraction are considered quantitatively. It is shown that errors in the lattice parameter and the effects of tilting the specimen or lens aberrations are not in practice limiting factors. The accuracy is limited usually by the measurement of the diffraction pattern but may be limited by error in the electron wavelength if the voltage of the electron microscope is not measured under the conditions of the experiment.