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We describe a system which is capable of mapping the relief of textile surfaces, by non contact optical means, designed to be used in textile engineering laboratories to study the alterations produced in fabrics by the action of dyes, shock, stress, and so on. The specific nature of these materials precludes the use of conventional profiling systems, which led us to develop a new method with the necessary versatility but reasonably immune to dispersion, diffraction and speckle, phenomena which usually make very difficult the application of optical methods to this situation. The method is based on the horizontal shift of the bright spot on an horizontal surface when this is illuminated with an oblique beam and moved vertically. In order to make the profilometry the sample is swept by an oblique laser beam and the bright spot position is compared with a reference position. The system is thus formed by an HeNe laser focused onto a reference surface (sample support) endowed of bidirectional motion obtained by two stepping motors which are controlled by a 8051 microcomputer that will also control the data acquisition and processing system, and it's forwarding to the working microcomputer. The laser beam incidence angle, the focusing system and the reception objective can be changed to increase the system fickleness.
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