Application of room-temperature infrared photo detectors in high-speed laser beam diagnostics of industrial CO2 lasers

摘要

Abstract: The paper presents applications of newly developedroom-temperature mercury based photo- detectors(single-element and array type) in the measurement ofinfrared CO$-2$/ laser radiation during materialprocessing. A specially designed measuring device todetermine the intensity profile of high-power CO$-2$/lasers in two perpendicular cross-sections with a time-resolution up to 10 kHz for a whole line-scan ispresented. The data-acquisition and analyzing equipmentbased on a digital-signal-processor (DSP) enables us tocalculate parameters which characterize the temporalstability of the laser mode on-line. Experimentalresults illustrate the possibilities of the device.Moreover, the time-resolved measurement of laser beamparameters during material processing serves as a toolto investigate the influence of the laser beam on thedynamic process behavior. Optical signals obtained fromthe laser beam welding process are correlated withlaser beam power variations to determine the grade ofinteraction. !8