Adaptive multibeam laser cutting of thin steel sheets with fiber laser using spatial light modulator

Laser cutting with multibeam diffraction pattern using an adaptive optics is studied. Infrared (IR) continuous single-mode fiber laser with maximum power of 200 W is applied to laser cutting of thin metal sheets, together with liquid crystal on silicon spatial light modulator (SLM). SLM can be used as the adaptive diffractive optical element, which can modify intensity profile of the laser beam almost arbitrary. In studies single Gaussian laser beam was divided into multiple spots. It was found out that with this way it is possible to enhance the cutting quality and also decrease pressure of the needed assist gas. Multibeam configuration enabled to laser cut burr free with 50% less protection gas pressure compared to single beam laser cutting with conventional optics. (C) 2014 Laser Institute of America.