New Noncontact Method for Evaluating Surface Roughness Parameters by Air-Caupled Ultrasound

摘要

A noncontact evaluation of surface roughness parameters, R_q and gamma_o, using air-coupled ultrasound has been presented. It has been shown that the R_q and gamma_o can be estimated from coherent and incoherent components of scattered waves. Air-coupled ultrasound can be used to measure surface roughness with a large range of roughness such as greater than 20 mu m, where the optics can not be applied.