Wavefront shaping with a Hadamard basis for scattering soil imaging

Journal Article · 13 January 2022 · Applied Optics

DOI: https://doi.org/10.1364/ao.442957 · OSTI ID:1860920

Wang, Dongping ^[1]; Poyneer, Lisa A. ^[1]; Chen, Diana ^[1]; Mark Ammons, S. ^[1]; Morrison, Keith D. ^[1]; Lee, Janghyuk ^[1]; Ly, Sonny S. ^[1]; Laurence, Ted A. ^[1]; Weber, Peter K.  ^[1]

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1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Here, soil is a scattering medium that inhibits imaging of plant-microbial-mineral interactions that are essential to plant health and soil carbon sequestration. However, optical imaging in the complex medium of soil has been stymied by the seemingly intractable problems of scattering and contrast. Here, we develop a wavefront shaping method based on adaptive stochastic parallel gradient descent optimization with a Hadamard basis to focus light through soil mineral samples. Our approach allows a sparse representation of the wavefront with reduced dimensionality for the optimization. We further divide the used Hadamard basis set into subsets and optimize a certain subset at once. Simulation and experimental optimization results demonstrate our method has an approximately seven times higher convergence rate and overall better performance compared to that with optimizing all pixels at once. The proposed method can benefit other high-dimensional optimization problems in adaptive optics and wavefront shaping.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Biological and Environmental Research (BER)
• Grant/Contract Number: AC52-07NA27344
• OSTI ID: 1860920
• Report Number(s): LLNL-JRNL-826634; 1041336
• Journal Information: Applied Optics, Journal Name: Applied Optics Journal Issue: 9 Vol. 61; ISSN 1559-128X
• Publisher: Optical Society of AmericaCopyright Statement
• Country of Publication: United States
• Language: English