Optical coherence tomography as a tool for non destructive quality control of multi-layered foils

Optical coherence tomography (OCT) was tested as a tool for an in-line quality control of multi-layered foils directly during the production process. To this end a portable high speed and high resolution spectral-domain OCT system was equipped with a specially designed probe head. The performance of the system and its ability to image samples moving laterally at high speed were successfully tested under laboratorial conditions. Subsequently the OCT system was implemented at a blown film extrusion line at the Innovation Headquarter of Borealis Polyolefine in Linz, Austria. The imaging sessions were performed during the actual production process and proved the capability of OCT to image and distinguish the individual layers in the multi-layered foils.