Beersiek, J.J.BeersiekSchulz, WolfgangWolfgangSchulz2022-03-082022-03-082003https://publica.fraunhofer.de/handle/publica/305777Treatment of materials with high energy radiation inducing a plasma, in particular, laser radiation (12) is claimed. The region of vapour capillaries of the workpiece (10) is observed with a depth of focus covering the entire workpiece thickness, while the time dependent intensity of plasma radiation is measured. The instantaneous plasma intensities are measured at least in places parallel to the axis (11) of the radiation (12). The measured values are related to predetermined parameters of the capillary geometry used to control the material treatment process. Also claimed is apparatus having at least two detectors (16', 16'') serving for measurement of instantaneous plasma intensities. USE - Used e.g. in welding installations. ADVANTAGE - Better results are obtained through improved control and monitoring of the treatment process.de608621patent1997-19741329