Wavefront engineering for controlled structuring of far-field intensity and phase patterns from multimodal optical fibers

Abstract: Adaptive optics methods have long been used to perform complex light shaping at the output of a multimode fiber (MMF), with the specific aim of controlling the emitted beam in the near-field. Gaining control of other emission properties, including the far-field pattern and the phase of the generated beam, would open up the possibility for MMFs to act as miniaturized beam splitting, steering components and to implement phase-encoded imaging and sensing. In this study, we employ phase modulation at the input of a MMF to generate multiple, low divergence rays with controlled angles and phase, showing how wavefront engineering can enable beam steering and phase-encoded applications through MMFs.