Super-resolution linear optical imaging in the far field

TL;DR

This paper demonstrates a novel far-field, linear-optical super-resolution imaging method that surpasses diffraction limits by analyzing spatial correlations through Hermite-Gaussian modes, enabling enhanced resolution without active interaction.

Contribution

It introduces the first proof-of-principle for a passive, far-field super-resolution technique based on mode analysis, expanding applicability to astronomy and biological imaging.

Findings

Achieved twofold resolution enhancement beyond diffraction limit.

Utilized 21 spatial modes in both transverse dimensions for imaging.

Validated the method through a proof-of-principle demonstration.

Abstract

The resolution of optical imaging devices is ultimately limited by the diffraction of light. To circumvent this limit, modern super-resolution microscopy techniques employ active interaction with the object by exploiting its optical nonlinearities, nonclassical properties of the illumination beam, or near-field probing. Thus, they are not applicable whenever such interaction is not possible, for example, in astronomy or non-invasive biological imaging. Far-field, linear-optical super-resolution techniques based on passive analysis of light coming from the object would cover these gaps. In this paper, we present the first proof-of-principle demonstration of such a technique. It works by accessing information about spatial correlations of the image optical field and, hence, about the object itself via measuring projections onto Hermite-Gaussian transverse spatial modes. With a basis of 21 spatial modes in both transverse dimensions, we perform two-dimensional imaging with twofold resolution enhancement beyond the diffraction limit.