Imaging through a thin scattering layer and jointly retrieving the point-spread-function using phase-diversity

TL;DR

This paper introduces a phase-diversity speckle imaging method that enables non-invasive imaging through scattering layers and simultaneous retrieval of the system's PSF and pupil function without guide-stars.

Contribution

It presents a novel phase-diversity technique inspired by astronomy, capable of estimating the PSF and pupil function in highly scattering systems from speckle patterns.

Findings

Successfully retrieves diffraction-limited images of hidden objects.

Simultaneously estimates the PSF and pupil function.

Operates without guide-stars or references.

Abstract

Recently introduced angular-memory-effect based techniques enable non-invasive imaging of objects hidden behind thin scattering layers. However, both the speckle-correlation and the bispectrum analysis are based on the statistical average of large amounts of speckle grains, which determines that they can hardly access the important information of the point-spread-function (PSF) of a highly scattering imaging system. Here, inspired by notions used in astronomy, we present a phase-diversity speckle imaging scheme, based on recording a sequence of intensity speckle patterns at various imaging planes, and experimentally demonstrate that in addition to being able to retrieve diffraction-limited image of hidden objects, phase-diversity can also simultaneously estimate the pupil function and the PSF of a highly scattering imaging system without any guide-star nor reference.