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The form of a crater, appearing during interaction of laser pulse with the surface of a metal sample, was obtained by stripe projection method. The factors that determine the topography of the crater were investigated. The model which permits us to describe the forming of the zone of destruction and to explain its relief was suggested. Velocities of the metal drops thrown out of the melted zone, the pressure which threw the drops and the gradient of pressure in the compressed gas at the surface of the target were evaluated. The increasing use of laser processing of materials is responsible for the growing interest in the elaboration of new methods of non-destructive diagnostics and control of the regime and results of technological process. That is why the physical phenomena resulting from the interaction of the radiation with solid excite a great interest. The processes that proceed in plasma cloud near the surface of the target (the `external problem') and in the melted zone (`the internal problem') are investigated rather completely. Less investigated are the processes proceeding directly on the surface of the irradiated sample. Moreover, a real shape of the melted area and of the crater appearing on the surface of the target was not radically investigated in detail. However, many parameters of both external and internal problems are determined exactly by the shape of the area of the interaction of radiation with matter. Our aim was non-contact (and, consequently, nondestructive) determination of the topography of the crater, appearing during the interaction of optical pulse with the surface of metal, investigation of processes proceeding during the forming of the zone of laser destruction and clarification of the factors that determine relief of the crater.
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