  The electron-diffraction pattern at a nonfluorescent target was observed by
Schwarz under attempts to modulate an electron beam by laser light. The pattern
was of the same color as the laser light. The analysis of the literature shows
there are the unresolved up to now significant contradictions between the
theory and the Schwarz experiments. To resolve these contradictions, the
interpretation of the Schwarz-Hora effect is considered, which is a development
of the idea formulated by Schwarz and Hora. It is supposed that the interaction
of electrons with the laser field inside a thin dielectric film is accompanied
not only by the processes of absorption and stimulated emission of photons but
also by formation of some metastable electron states in which the captured
photons can be transferred with a following emission at the target.
