Mechanical lapping is still used widely as one of fine finishings of material surfaces in spite of increasing applications of chemical polishing. In the mechanical operation, fine diamond particles play an important role because of their high lapping performance except for the presence of occasional scratching which should be solved or mitigated by investigating particle characteristics and lapping procedures. On the other hand, the approach to comprehensive analysis of surface profiles recorded during lapping process needs to be considered in addition to the statistical standards such as average surface roughness, maximum peak height, 10-point height, etc. It is a useful trial to apply wave analyses aided with functional transformation for identification of the characteristic parameters of lapped surfaces. Hence, the profiles were analyzed for surfaces prepared under several differently shaped diamond particles within narrow size ranges. In this report, the results of the mathematical analysis of the profiles obtained from 2D scanning of lapped surfaces, which include the directional roughness, are discussed in terms of surface uniformity, asymmetricity, waviness evaluation, etc. These surface characteristics are closely related with the shape parameters of grinds (diamond particles) such as elongation, polygonality, irregularity, etc. (C) 2003 Elsevier Science B.V. All rights reserved.