METHOD AND APPARATUS FOR CHECKING THE CONDITION OF A PROTECTIVE GLASS IN CONNECTION WITH LASER MACHINING

摘要

The invention relates to a method and an apparatus for checking the condition of a protective glass (3) arranged between the workpiece (2) and the laser optics (1) in a laser machining system and through which protective glass the machining laser beam (6) is arranged to pass. A photo-detector (8) is arranged in connection with the protective glass (3) to detect radiation scattered by dirt and dust particles (5) on the protective glass surface.