EVALUATION OF THE SURFACE-ROUGHNESS OF CYSTINE STONES USING A VISIBLELASER-DIODE SCATTERING APPROACH

To understand the processes of fragmentation and the chemical reactivi ty of solids, proper characterization of surface topography is crucial . This paper describes a non-destructive technique of quantifying the surface roughness of cystine renal stones, using visible laser diode s cattering and fractal geometry. Fragments of cystine stones were mount ed on microscope slides and coated by a carbon-sputtering apparatus. T he slides were placed under a dynamic active-vision system, using a vi sible laser diode to measure three-dimensional surface coordinates. Th e data obtained were analyzed by fractal geometry. Surface fractal dim ensions were determined by the variation method. The results showed th at the surface of a compact-size sample can be evaluated quantitativel y. The technique is valuable for the accurate presentation of surfaces in three dimensions.