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In this paper we present results related to the development of an alternative and non-destructive method for determining and mapping the etch pits density, in real time, by using digital imaging processing in association with an optical system. The density and distribution of the dislocation etch pits were obtained by the specular reflection produced by either a He-Ne laser or a white light on an etched semiconductor material surface. As the pits related to dislocations have a typical geometric form according to crystallographic plane of the surface they become more evident than other defects and, as a consequence this allows to reach selectivity for this specific defect by the system. The efficiency of the suggested method was accomplished by comparing the results obtained with conventional analysis done by optical microscopy. The proposed automated system demonstrated to be capable of covering large surface areas very rapidly, if compared to a traditional method in view of the fact that by using optical microscopy the density and distribution of defects can be determined only in the small regions which makes the mapping of the entire sample laborious. Furthermore, this system can be easily adapted to a line production providing direct qualitative and quantitative information on the substrate quality.