Diffuse Maxwellian illumination for safe wide-field retinal Doppler holography

Zofia Bratasz; Olivier Martinache; Yohan Blazy; Angèle Denis; Coline Auffret; Jean-Pierre Huignard; Ethan Rossi; Jay Chhablani; José-Alain Sahel; Sophie Bonnin; Rabih Hage; Patricia Koskas; Damien Gatinel; Catherine Vignal; Amelie Yavchitz; Vivien Vasseur; Ramin Tadayoni; Claire Ducloux; Manon Ortoli; Marvin Tordjman; Sarah Tick; Sarah Mrejen; Michel Paques; Michael Atlan

arXiv · 2212.13347

Diffuse Maxwellian illumination for safe wide-field retinal Doppler holography

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Abstract

We report a diffuse Maxwellian illumination scheme for wide-field retinal laser Doppler holography. Inserting an engineered diffuser in the illumination arm transforms a spatially concentrated near-infrared laser focus into an angularly diversified illumination pattern, thereby reducing local irradiance near the anterior segment while preserving coherent interferometric detection. This configuration allows the eyepiece to be positioned closer to the cornea, increasing the digitally reconstructed retinal field of view without producing a localized corneal hot spot. We compare three illumination geometries: focused non-diffuse illumination, diffuse illumination at the same cornea--eyepiece distance, and diffuse Maxwellian illumination. Diffuse Maxwellian illumination expands the retinal field of view while preserving Doppler contrast in broad and high-frequency fluctuation bands. Light-hazard assessment is limited to the current ophthalmic standards ISO 15004-2:2024 and ANSI Z80.36-2021. Based on measured beam profiles, the recommended operating power at 852 nm is set by the most restrictive relevant exposure condition among the assessed anterior-segment, iris, and retinal limits. These results support diffuse illumination as a practical route toward safer, non-mydriatic, wide-field Doppler holography of the human retina.

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Zofia Bratasz, Olivier Martinache, Yohan Blazy, Angèle Denis, Coline Auffret, Jean-Pierre Huignard, Ethan Rossi, Jay Chhablani, José-Alain Sahel, Sophie Bonnin, Rabih Hage, Patricia Koskas, Damien Gatinel, Catherine Vignal, Amelie Yavchitz, Vivien Vasseur, Ramin Tadayoni, Claire Ducloux, Manon Ortoli, Marvin Tordjman, Sarah Tick, Sarah Mrejen, Michel Paques, Michael Atlan. 2026-05-15. Diffuse Maxwellian illumination for safe wide-field retinal Doppler holography. https://arxiv.org/abs/2212.13347

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