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arXiv · 2406.00122

$\textit{In vivo}$ fundus imaging and computational refocusing with a diffuser-based fundus camera

Corey Simmerer·Marisa Morakis·Lei Tian·Lia Gomez-Perez·T. Y. Alvin Liu·Nicholas J. Durr
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Abstract

Significance: Access to diagnostic eye care could be expanded with high-throughput and easy-to-use tools. Phase mask-based imaging may improve the fundus camera by enabling computational refocusing with no moving parts. While phase mask-based imaging has been demonstrated in a model eye, this approach has not been shown $\textit{in vivo}$. Aim: A computational fundus camera was designed, constructed, and evaluated with the goal of determining the feasibility and performance of phase mask-based computational imaging of the $\textit{in vivo}$ fundus. Approach: A holographic diffuser was introduced in a modified commercial fundus camera at a plane conjugate to the ocular pupil, resulting in a linear and shift-invariant point spread function that varies with refractive error. The image could be digitally refocused across a range of $\geq\pm$ 10 diopters of defocus error. The device was tested for ocular safety, and a human imaging pilot study was performed. Results: The device captured and digitally refocused color human fundus images. The field of view was $\geq$35 degrees and resolution was 7.7-9.6 line pairs per mm. Conclusions: We present the first $\textit{in vivo}$ diffuser-based fundus images, demonstrating the feasibility of computational imaging for ocular diagnostics.

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Corey Simmerer, Marisa Morakis, Lei Tian, Lia Gomez-Perez, T. Y. Alvin Liu, Nicholas J. Durr. 2024-05-31. $\textit{In vivo}$ fundus imaging and computational refocusing with a diffuser-based fundus camera. https://arxiv.org/abs/2406.00122

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