Interleaved diffractive networks for information transfer through random diffusers

TL;DR

This paper presents a novel interleaved diffractive optical network that enables robust, all-optical transfer of information through random diffusers, validated both numerically and experimentally, with potential applications in imaging and communications.

Contribution

The work introduces a cascaded, passive diffractive network architecture optimized for information transfer through unknown diffusers, combining optical and digital methods for enhanced robustness.

Findings

Achieved reliable optical information recovery through random diffusers.

Demonstrated superior reconstruction with hybrid optical-digital system.

Validated system performance experimentally in the visible spectrum.

Abstract

Transferring optical information through random diffusers is a critical yet challenging task. In this work, we introduce a cascaded diffractive optical network for information transfer through random and unknown diffusers, achieved through a series of passive, structured layers physically interleaved within the scattering medium. These interleaved diffractive layers are optimized to mitigate the scattering process without requiring digital computing. The performance of this all-optical system was quantified as a function of several physical parameters, including the diffractive processor's depth, the physical layout of the diffractive layers, and the statistical properties of the scattering medium. To further enhance the performance and robustness of information transfer through a scattering medium, we also developed a hybrid (optical-digital) system that coupled the diffractive processor with a jointly trained digital neural network, which was shown to achieve superior reconstruction fidelity even when the input object information was subjected to unknown random rotations, shifts, and scaling. We also experimentally validated this system using a fabricated multi-layer diffractive system in the visible spectrum, demonstrating reliable information recovery through random diffuser layers. Our numerical and experimental results demonstrate the capabilities of an interleaved diffractive processor architecture to recover optical information through volumetric diffusive media, which can find applications in biomedical imaging, telecommunications, and remote sensing.