Photonic integrated circuits for astronomy: A formal description of an integrated photonics-based wavefront sensor (IP-WFS)

TL;DR

This paper introduces a novel integrated photonics-based wavefront sensor for astronomy that measures phase differences directly, avoiding image formation, and demonstrates its potential through mathematical modeling and simulations.

Contribution

It presents a new integrated photonics wavefront sensor that enables direct phase measurement, improving resolution and accuracy in astronomical wavefront sensing.

Findings

Mathematical model of the proposed wavefront sensor was developed.

Simulations confirmed the sensor's physical behavior and operational factors.

Abstract

Context. Solar wavefront sensing has been a challenge for astrophysical instrumentalists, due to the low contrast between the Sun and the sky background compared to night-time observations, which limits the performance of adaptive optics systems. Aims. Wavefront correction in solar physics requires the analysis of extended images; meanwhile, at night the displacement of a punctual object is analysed. This technique limits the spatial resolution, and therefore the accuracy in the wavefront reconstruction. Methods. To solve this problem, a new method of direct wavefront sensing without the need for image formation was explored for this work. A novel and promising technology called integrated photonics was used to accomplish this task. It allows the direct measurement of phase differences across the wavefront without the need to form images, using the principle of interferometry. This technology offers a low-consumption, miniaturised solution to astrophysical problems. Results. For this work a mathematical model was derived to characterise the behaviour of the proposed wavefront sensor. The proposed system was verified and simulated using a Python-based adaptive optics simulator. These simulations demonstrate the physical behaviour of the proposed wavefront sensor and highlight the factors that must be taken into account for its correct functioning.