The LINESCAN is a system capable to analyse continuously 100% production of whatever material in film, foil, or having a flat surface. By using this system, it is possible an in process detection of surface defects for example of laminated plastics, metallized films, non-wovens, opaque or transparent films, float glass. In particular, it is possible to know position of each defect detected in cartesian coordinates, compared to the border of roll (X axis) and to the begginig of the roll (Y axis), and to classify it.