We developed a small and compact system of diode lasers, which can be inserted into the lower tools of a bending press. The parts of the system allow easy plug and play operation and can be installed for any bending length. The diode laser, which is based on 200 W laser bars on microchannel cooler, allows the heating of sheet metals in the forming zone shortly before and during the bending process. There is no unnecessary heating of other parts of the bending equipment, no wear of the tool, and, if properly done, no damage of the surface of the metal. The power per bending length is 16 kW/m.

Testing of a reflective diffractive optical element (DOE) as part of specific CO2 laser equipment Oerlikon OPL 2000 for metallic materials modification was performed. The power density distribution in a plane located behind the DOE focal plane has been measured. It was found that DOEs make it possible to form a predetermined beam power density profile and to perform the transformation of laser energy, chosen by calculation previously. The use of these optical elements in the laser material treatment reveals new possibilities for controlling properties and operational characteristics of processed components. Additional redistribution of the beam power to edges of the laser spot is achieved by increasing the proportion of energy reflected by DOE peripheral zones, for example, by increasing the aperture of the focusable beam. It is proposed using a telescopic system of two lenses to change the aperture of the laser beam focusable by the DOE.

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We present a new approach for quality control in laser material processing. By means of an active optical element (SCPEM -Single Crystal PhotoElastic Modulator) the emitted thermal radiation from the interaction zone of the focused laser radiation with the material surface is to be detected in order to determine a correlation to the process parameters from the polarisation state of the radiation. Due to the dependence of polarised radiation on the emission angle, the inclination of the interaction zone in the observed area can be deduced. For this purpose, an optomechanical setup for measuring two orthogonal polarisation directions of the emitted thermal radiation has been developed and a data acquisition system has been implemented. The amplitudes of two orthogonal polarisation directions could be determined from the signal modulated by the SCPEM during tests on different experimental setups. From the ratio of these polarisation components, emission angles can be derived using the Fresnel equations.