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arXiv · 2410.15692

Shot-noise limited, 10 MHz swept-source optical coherence tomography for retinal imaging

Sacha Grelet·Alejandro Martinez Jimenez·Patrick B. Montague·Adrian Podoleanu
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Abstract

Akinetic swept-sources are essential for high-speed optical coherence tomography (OCT) imaging. Time-stretched supercontinuum (TSSC) lasers have proven to be efficient for multi-MHz swept-sources. However, lack of low-noise broadband lasers and of large dispersion devices in the water low-absorption band at 1060 nm have limited the biomedical applications of TSSC lasers. In this letter, an approach to tune the wavelength around 1050 nm over 90 nm with low-noise at 10 MHz is presented. This is based on all-normal dispersion (ANDi) supercontinuum dynamics, and employs a long chirped fiber Bragg grating (CFBG) to time-stretch a broadband pulse with a duty cycle of 93 %. Retinal images are demonstrated, with a sensitivity of 84 dB - approaching the shot noise limit. We believe this high-speed low-noise swept-source will greatly promote the development of OCT techniques for biomedical applications.

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Sacha Grelet, Alejandro Martinez Jimenez, Patrick B. Montague, Adrian Podoleanu. 2024-10-21. Shot-noise limited, 10 MHz swept-source optical coherence tomography for retinal imaging. https://arxiv.org/abs/2410.15692

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