As shown by C. L. Schaefer and L. Bergmann in 1934, ultrasonic elastograms may be obtained by diffraction of light transmitted through crystal samples that are excited to high‐frequency vibrations. The elastic constants of a number of cubic crystals (KCl, KBr, Kl, NaCl, NaBr, NaF, RbCl, RbBr, LiF, andCaF2) are determined by this method. An attempt is made to interpret the specific form of the resulting elastograms from the lattice structure of the crystals.