Application of He-Ne laser in surface metrology of porous construction materials

Application of laser radiation (He-Ne laser) in surface metrology of porous construction materials is relatively new concept. Non-contact measurement of surface alterations is based on analysis of the reflected light parameters. Although such analysis can be very complex due to highly developed roughness of surfaces they proved to be very informative. In this paper, two methods - laser speckle method and reflected light intensity method are presented and compared. The average surface modification factor, obtained from the laser speckle method and from reflected light intensity method shows a very good correlation.