2021/07/22 by Alba M. Paniagua-Díaz, William L. Barnes, Paniagua-Diaz, Alba M. +3 · 1 citation
Engineering · Physics and Astronomy · #Advanced Optical Imaging Technologies #FOS: Physical sciences #Optical Coherence Tomography Applications #Optics (physics.optics) #Random lasers and scattering media
paper · pdf · doi:10.48550/arxiv.2107.10601
openalex publication_date 2021/07/22 · openalex created_date 2022/07/25 · openalex updated_date 2026/07/28
A perfectly collimated beam can be spread out by multiple scattering, creating a speckle pattern and increasing the etendue of the system. Standard optical systems conserve etendue, and thus are unable to reverse the process by transforming a speckle pattern into a collimated beam or, equivalently, into a sharp focus. Wavefront shaping is a technique that is able to manipulate the amplitude and/or phase of a light beam, thus controlling its propagation through such media. Wavefront shaping can thus break the conservation of etendue and, in principle, reduce it. In this work we study how much of the energy contained in a fully developed speckle pattern can be converted into a high quality (low M2) beam, and discuss the advantages and limitations of this approach, with special attention given to the inherent variability in the quality of the output due to the multiple scattering.