Real time phase imaging with an asymmetric transfer function metasurface

TL;DR

This paper introduces a metasurface that uses photonic spin-orbit coupling to enable real-time, all-optical phase imaging with high contrast, eliminating the need for bulky components or post-processing, suitable for biological and wavefront applications.

Contribution

The authors develop a metasurface with an asymmetric transfer function that allows direct, real-time phase imaging through an all-optical approach, advancing compact imaging technology.

Findings

Demonstrated high contrast pseudo-3D images of phase variations

Achieved real-time phase imaging without post-processing

Validated the device's effectiveness experimentally

Abstract

The conversion of phase variations in an optical wavefield into intensity information is of fundamental importance for optical imaging technology including microscopy of biological cells. While conventional approaches to phase-imaging commonly rely on bulky optical components or computational post processing, meta-optical devices have recently demonstrated all-optical, ultracompact image processing methods. Here we describe a metasurface that exploits photonic spin-orbit coupling to create an asymmetric optical transfer function for real time phase-imaging. The effect of the asymmetry on transmission through the device is demonstrated experimentally with the generation of high contrast pseudo-3D intensity images of phase variations in an optical wavefield without the need for post-processing. This non-interferometric method has potential applications in biological live cell imaging and real-time wavefront sensing.