Optical phase mining by adjustable spatial differentiator

TL;DR

This paper introduces an optical phase mining technique using adjustable spatial differentiation that analyzes polarization in reflected light to recover phase distributions without complex devices.

Contribution

It presents a novel, simple method for phase retrieval based on polarization analysis and virtual light sources, avoiding resonance or material dispersion dependencies.

Findings

Successfully recovered phase of transparent objects

Demonstrated a polarization-based phase mining method

Applicable across a broad frequency range

Abstract

Phase is a fundamental resource for optical imaging but cannot be directly observed with intensity measurements. The existing methods to quantify a phase distribution rely on complex devices and structures. Here we experimentally demonstrate a phase mining method based on so-called adjustable spatial differentiation, just generally by analyzing the polarization in light reflection on a single planar dielectric interface. With introducing an adjustable bias, we create a virtual light source to render the measured images with a shadow-cast effect. We further successfully recover the phase distribution of a transparent object from the virtual shadowed images. Without any dependence on resonance or material dispersion, this method directly stems from the intrinsic properties of light and can be generally extended to a board frequency range.