File:Brillouin-zone construction by 300keV electrons.jpg

English: Selected area electron diffraction (SAED) pattern of a thick Si specimen with many diffusely-scattered 100keV electrons, and a beam direction nearly parallel to the Si<111> zone.

The λ ≈ 0.0370 Å electron-wavelength makes the radius 1/λ Ewald-sphere nearly planar on the scale of the inner-star radius g₂₂₀ ≡ 1/d₂₂₀ ≈ 1/1.92Å, and the beam half-angle facilitates weak excitation of many Bragg-reflections even though no reflections are at the Bragg-condition (where a Kikuchi-band in the star-pattern e.g. of width θ_scatt = 2θ_Bragg = 2asin[λ/(2d₂₂₀)] ≈ 19.2 mrad would have been shifted to intersect both the incident beam's central dot and a diffraction spot).

These electrons either had enough leptonic-imagination by themselves to construct the 2D Wigner-Seitz cell^[1] (lattice-point bisectors) for this reciprocal-lattice slice, or else Brillouin-zone surfaces in a crystal are so real that they can be directly imaged. What do you think?