Adaptive phase correction of dynamic multimode beam based on modal decomposition

We propose and demonstrate a method for the adaptive phase correction of dynamic multimode fiber beams. The phase of incident beam is reconstructed in real-time based on the complete modal information, which obtained by using the modal decomposition of correlation filter method. For the proof of principle both of the modal decomposition and the phase correction arc implemented using the same computer-generated hologram, which was encoded into a phase-only spatial light modulator. We demonstrate the phase correction of dynamic multimode beam at a rate of 5 Hz and achieve a 1.73-fold improvement on the average power-in-the-bucket The experimental results indicate the feasibility of the real-time phase correction for the large mode area fiber laser by adaptive optics. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement