Synthetic optical holography for in-depth imaging of optical vortices in speckle patterns

A Di Donato,G Orlando,M Tamagnone,L Cavanini,L Pierantoni,L Criante,G Ippoliti,D Mencarelli,A Morini,M Farina

doi:10.1063/1.5053564

Abstract

In this paper, we report a novel approach based on a lensless Synthetic Optical Holography (SOH) that is aimed to recover the complex scattered field from buried surfaces at different wavelengths with sub-nanometric spectral resolution, without affecting the phase retrieval in depth. The proposed technique is applied to characterize and image the field scattered from a rough embedded surface of a microfluidic channel. The real and imaginary part of the random complex field revealed the presence of 2D optical vortices at each location in which a phase singularity is located. A statistical study of optical vortices is presented and the high spectral resolution is exploited to study the behavior of topological charges with the frequency shift.

Highlights

We report a novel approach based on a lensless Synthetic Optical Holography (SOH) that is aimed to recover the complex scattered field from buried surfaces at different wavelengths with sub-nanometric spectral resolution, without affecting the phase retrieval in depth
Synthetic Optical Holography (SOH) is a technique recently introduced with the aim to combine Digital Off-axis Holography (DOH) and Scanning Probe Microscopy (SPM)
On the other side, Scanning Probe Microscopy includes different techniques and some of these were recently combined with DOH,8 borrowing from Microwave Holography, the concept of Synthetic Reference Wave already introduced in Synthetic Aperture Radars

Summary

Introduction

Synthetic Optical Holography (SOH) is a technique recently introduced with the aim to combine Digital Off-axis Holography (DOH) and Scanning Probe Microscopy (SPM).

Results

Conclusion