Microwave Speckle Contrast for Surface Roughness Measurements

Microwave speckle contrast measurements can be used to perform remote determination of macroscopic surface roughness. This procedure is non-contact and can be performed through windows of certain dielectric materials. Therefore it has many potential applications in process control and corrosion detection. Measurements of root mean squared (rms) roughness up to 7.5 millimeters have been made using the microwave system.