Features of spherical x-ray wave diffraction by a low angle twist boundary perpendicular to the crystal surface

The diffraction behavior of a low-angle twist boundary was studied when the crystal was irradiated with an X-ray point source. It is shown that when radiation focused inside a crystal, thanks to the dislocation structure of the defect wall, the vertical divergence can be reduced so much that the size of the focus in this direction is significantly smaller than in the horizontal direction. This circumstance can be used to create X-ray optical elements