Plane-wave X-ray images of dislocations parallel to the diffraction vector

The formation of plane wave images of dislocations parallel to the diffraction vector is investigated. With a wedge‐shaped sample the development of the contrast in dependence on the crystal thickness is revealed. Under low absorption conditions a modification of the pendellösung fringes is observed experimentally and explained theoretically. Under high absorption conditions the fine structure of dislocation images is studied. Moreover under the same conditions a modification of dislocation images in the strain field of another dislocation located beneath the first ones is revealed. This phenomenon is studied both, analytically in the ray optics approximation and by computer simulations. Some new rules for the complete Burgers vector determination are proposed. [Russian Text Ignored]