Electron microscopy images of rectilinear inclined dislocations crossing the free surface at arbitrary angles are theoretically investigated. The influence of some factors, such as the Burgers vector orientation, the dislocation inclination, the image type, etc. on the electron microscopy image are studied. Images of close‐to‐the‐surface dislocations surrounded by impurity atmospheres are discussed.

A model is proposed for the impurity‐atom cloud formed near an edge dislocation lying parallel to the surface taking into account the basic physical features of the real cloud. On the basis of the regularities obtained for the distribution of the displacement fields of the present model the eatures of the electron‐microscopy images are studied theoretically for a dislocation with a cloud. The presence of the cloud leads to a decrease of the edge intensity of the dislocation image independent of its bedding depth and to a change of the contrast sign at some depths. The diffraction conditions are found where these effects are mostly marked.

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A direct method of calculating the deformation fields of an inclined dislocation in a semi‐infinite medium is developed. A quantitative analysis of the elastic field distribution shows that a free surface localizes elastic fields near the dislocation nuclei and reduces them at large distances. Redistribution of elastic fields results in a sign inversion of some components of the stress tensor. For a screw dislocation in the region close to the surface there appears dilatation with an amplitude comparable with that of an edge dislocation.

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