Development of Non-contact Surface Roughness Measurement in Last Decades

Surface roughness measurement is widely required in the quality assurance of manufacturing processes. And a number of surface roughness measurement methods have been developed since long ago. This paper introduces four kind typical non-contact measurement methods, which have been widely investigated in the last decades for precise measurement. They are microscopes methods, interferometry methods, diffraction methods, and methods based on scattering modeling. Methods of each kind are reviewed, furthermore the advantages and disadvantages of each kind are analyzed.