Surface roughness characterisation using optical feedback interferometry
The characterisation of surface roughness is important in process control and metrology. A simple, low cost sensor which can be used for this measurement is one based on laser optical feedback interferometry. A target containing samples of similar abrasive paper with different levels of roughness was characterised using a sensor based on this technique, and the resulting measurements show that the standard deviation of the optical feedback signal was proportional to the roughness of the surface.