A laser machining method for machining a workpiece by applying a laser beam thereto, comprises a protective film coating step of coating a surface to be machined, of the workpiece with a protective film; a laser beam shining step of applying a laser beam to the workpiece through the protective film;...http://www.google.fr/patents/US20040112880?utm_source=gb-gplus-shareBrevet US20040112880 - Laser machining method
