Adaptive optics imaging with a pyramid wavefront sensor for visual science

Elisabeth Brunner; Julia Shatokhina; Muhammad Faizan Shirazi; Wolfgang Drexler; Rainer Leitgeb; Andreas Pollreisz; Christoph K. Hitzenberger; Ronny Ramlau; Michael Pircher

arXiv · 2106.11052

Adaptive optics imaging with a pyramid wavefront sensor for visual science

Elisabeth Brunner·Julia Shatokhina·Muhammad Faizan Shirazi·Wolfgang Drexler·Rainer Leitgeb·Andreas Pollreisz·Christoph K. Hitzenberger·Ronny Ramlau·Michael Pircher

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Abstract

The pyramid wavefront sensor (P-WFS) has replaced the Shack-Hartmann (SH-) WFS as sensor of choice for high performance adaptive optics (AO) systems in astronomy because of its flexibility in pupil sampling, its dynamic range, and its improved sensitivity in closed-loop application. Usually, a P-WFS requires modulation and high precision optics that lead to high complexity and costs of the sensor. These factors limit the competitiveness of the P-WFS with respect to other WFS devices for AO correction in visual science. Here, we present a cost effective realization of AO correction with a non-modulated PWFS and apply this technique to human retinal in vivo imaging using optical coherence tomography (OCT). P-WFS based high quality AO imaging was, to the best of our knowledge for the first time, successfully performed in 5 healthy subjects and benchmarked against the performance of conventional SH-WFS based AO. Smallest retinal cells such as central foveal cone photoreceptors are visualized and we observed a better quality of the images recorded with the P-WFS. The robustness and versatility of the sensor is demonstrated in the model eye under various conditions and in vivo by high-resolution imaging of other structures in the retina using standard and extended fields of view.

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Elisabeth Brunner, Julia Shatokhina, Muhammad Faizan Shirazi, Wolfgang Drexler, Rainer Leitgeb, Andreas Pollreisz, Christoph K. Hitzenberger, Ronny Ramlau, Michael Pircher. 2021-06-28. Adaptive optics imaging with a pyramid wavefront sensor for visual science. https://arxiv.org/abs/2106.11052

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