Robust Super-Resolution Imaging Based on a Ring Core Fiber with Orbital Angular Momentum

TL;DR

This paper introduces a robust super-resolution imaging system using a ring core fiber with orbital angular momentum, enhancing image quality and resilience against environmental disturbances, with applications in biological and industrial imaging.

Contribution

The paper presents a novel RCF-OAM imaging system that combines weakly-coupled OAM modes and a neural network for improved robustness and resolution in challenging environments.

Findings

System achieves high-resolution biological image transmission.

Imaging system demonstrates robustness against environmental perturbations.

Potential applications in biological imaging and industrial testing.

Abstract

Single fiber imaging technology offers unique insights for research and inspection in difficult to reach and narrow spaces. In particular, ultra-compact multimode fiber (MMF) imaging, has received increasing interest over the past decade. However, MMF imaging will be seriously distorted when subjected to dynamic perturbations due to time-varying mode coupling, and the imaging of space objects via Gaussian beam will be relatively degraded at the edge due to insufficient contrast. Here, a robust super-resolution imaging method based on a ring core fiber (RCF) with orbital angular momentum (OAM) has been proposed and experimentally demonstrated. The OAM modes propagating in the RCF form a series of weakly-coupled mode groups, making our imaging system robust to external perturbations. In addition, a spiral phase plate is used as a vortex filter to produce OAM for edge enhancement, thus improving the image resolution. Furthermore, a few-shot U-Transformer neural network is proposed to enhance the resilience of the developed RCF-OAM imaging system against environmental perturbations. Finally, the developed RCF-OAM imaging system achieves biological image transmission, demonstrating the practicality of our scheme. This pioneering RCF OAM imaging system may have broad applications, potentially revolutionising fields such as biological imaging and industrial non-destructive testing.