Phase-shifting technique for improving the imaging capacity of sparse-aperture optical interferometers

TL;DR

This paper introduces a phase-shifting multi-aperture interferometer design that enhances astrophysical imaging by enabling quick, high-resolution snapshot imaging with simplified optics and the potential to combine hundreds of telescopes on a single detector.

Contribution

The paper presents a novel phase-shifting technique for sparse-aperture interferometers, improving imaging capacity and simplifying design for large telescope arrays.

Findings

Numerical simulations show coupling of hundreds of telescopes on a 4K x 4K detector.

The design offers high radiometric efficiency and a wide field of view.

Preliminary calibration procedures enable instrumental error characterization.

Abstract

In this paper, we describe the principle of a multi-aperture interferometer that uses a phase-shifting technique and is suitable for quick, snapshot imaging of astrophysical objects at extreme angular resolution through Fourier inversion. A few advantages of the proposed design are highlighted, among which are radiometric efficiency, Field of View equivalent to those of Fizeau interferometers, and a preliminary calibration procedure allowing characterization of instrumental errors. For large telescope numbers, the proposed design also results in considerable simplification of the optical and mechanical design. Numerical simulations suggest that it should be possible to couple hundreds of telescopes on a single 4K x 4K detector array, using only conventional optical components or emerging technologies.