The functionalisation of surfaces through the creation of periodic micro- and nanopatterns can be achieved using a wide range of manufacturing processes. Among these, those based on laser technology stand out for their high throughput, high degree of flexibility and resolutions even below the diffraction limit. When this process is implemented in an industrial context, monitoring of the laser generated structures becomes crucial for quality control of the resulting surface, ensuring stability and repeatability during production. For industrial monitoring, methods based on scatterometry offer significant advantages because these approaches are non-contact, non-destructive, limited only by camera acquisition and processing times, and can resolve features down to the sub-microscale.

In this study, an optical setup based on scatterometry was employed to monitor the surface of laser microstructured stainless steel plates. This system is based on a low power light source illuminating the sample surface. The scattered light is then collected by a lens system and focused onto a CCD camera where characteristic patterns are recorded depending on the surface topography. Once the images are recorded by the CCD camera, the spatial periods, structure depth and orientation are estimated from the position and intensity of the diffraction orders.