Lensless Wiener-Khinchin telescope based on high-order spatial autocorrelation of thermal light

TL;DR

This paper introduces a lensless imaging method using high-order spatial autocorrelation of thermal light, enabling resolution recovery in complex media where traditional first-order correlation methods fail.

Contribution

It demonstrates for the first time that high-order correlations can recover point-to-point correspondence in challenging imaging scenarios and proposes a novel lensless telescope based on this principle.

Findings

High-order correlation analysis enables resolution determination in complex media.

The proposed lensless telescope can acquire images with a single snapshot.

Applicable to fields like X-ray astronomy and imaging through scattering media.

Abstract

The resolution of a conventional imaging system based on first-order field correlation can be directly obtained from the optical transfer function. However, it is challenging to determine the resolution of an imaging system through random media, including imaging through scattering media and imaging through randomly inhomogeneous media, since the point-to-point correspondence between the object and the image plane in these systems cannot be established by the first-order field correlation anymore. In this paper, from the perspective of ghost imaging, we demonstrate for the first time to our knowledge that the point-to-point correspondence in these imaging systems can be quantitatively recovered from the high-order correlation of light fields, and the imaging capability, such as resolution, of such imaging schemes can thus be derived by analyzing high-order correlation of the optical transfer function. Based on this theoretical analysis, we propose a lensless Wiener-Khinchin telescope based on high-order spatial autocorrelation of thermal light, which can acquire the image of an object by a snapshot via using a spatial random phase modulator. As an incoherent imaging approach illuminated by thermal light, lensless Wiener-Khinchin telescope can be applied in many fields such as X-ray astronomical observations.