Axial intensity increase of light passing through multimode fiber by two-stage correlation method

摘要

The paper reports the results of light beams transformation at multimode fibers exit to increase axial light intensity. It is achieved by smoothing of the output wavefront. To eliminate wavefront inhomogeneity we used two-stage correlation method of laser beams transformation. The main elements of two-stage correlation system are the spatial modulator and the hologram. The effect of the two-stage both on laser modes and on output fields of the multimode fiber were simulated and experimentally studied. The investigation has established that considerable increases of the axial intensity is achieved for the fields having mode content which is similar to the mode contents at the hologram recording stages. At the same time, the intensity increase is actualized for wide set of the specific field distributions at the input of system.