Surface roughness measurement by depolarization method

A fiber profilometer based on a polarization manipulation technique is developed to measure both surface roughness and profile simultaneously. The depolarization effect caused by the surface scattering is utilized to characterize the roughness properties. A theoretical model is developed to study the second-order dependence of depolarization to quantify the surface roughness characteristics. Experiments are carried out to demonstrate and verify the relationship between the depolarization and the surface roughness. This technique can simultaneously achieve the properties of the surface profile and roughness based on a fiber profilometer system.