The role of projection operators in the theory of N-beam diffraction and the inversion of three-beam elastic scattering intensities

Commencing from a projection-operator description of N-beam diffraction, the mathematical basis for the recovery of phase and amplitude information from a three-beam convergent-beam electron diffraction pattern is given for both the centrosymmetric and noncentrosymmetric cases. The algebra is available in Mathematica Notebook form from the URL ftp://ftp.physics.uwa.edu.au/pub/EMC/3BeamAlgebra.nb.