Widefield Optical Coherence Tomography by Electro-optical Modulation

TY - JOUR

T1 - Widefield Optical Coherence Tomography by Electro-optical Modulation

AU - Urban, Dorian R.

AU - Novak, Pavel

AU - Preciado, Miguel A.

AU - Vettenburg, Tom

N1 - Publisher Copyright: © 2024 Optica Publishing Group (formerly OSA). All rights reserved.

PY - 2024/10/28

Y1 - 2024/10/28

N2 - Optical coherence tomography (OCT) is a unique imaging modality capable of axial sectioning with a resolution of only a few microns. Its ability to image with high resolution deep within tissue makes it ideal for material inspection, dentistry, and, in particular, ophthalmology. Widefield retinal imaging has garnered increasing clinical interest for the detection of numerous retinal diseases. However, real-time applications in clinical practice demand the contrast of swept-source OCT at scan speeds that limit their depth range. The curvature of typical samples, such as teeth, corneas, or retinas, thus restricts the field-of-view of fast OCT systems. Novel high-speed swept sources are expected to further improve the scan rate; however, not without exacerbating the already severe trade-off in depth range. Here, we show how, without the need for mechanical repositioning, harmonic images can be rapidly synthesized at any depth. This is achieved by opto-electronic modulation of a single-frequency swept source laser in tandem with tailored numerical dispersion compensation. We demonstrate experimentally how real-time imaging of highly-curved samples is enabled by extending the effective depth range 8-fold. Even at the scan speed of a 400 kHz swept source, harmonic OCT enables widefield retinal imaging.

AB - Optical coherence tomography (OCT) is a unique imaging modality capable of axial sectioning with a resolution of only a few microns. Its ability to image with high resolution deep within tissue makes it ideal for material inspection, dentistry, and, in particular, ophthalmology. Widefield retinal imaging has garnered increasing clinical interest for the detection of numerous retinal diseases. However, real-time applications in clinical practice demand the contrast of swept-source OCT at scan speeds that limit their depth range. The curvature of typical samples, such as teeth, corneas, or retinas, thus restricts the field-of-view of fast OCT systems. Novel high-speed swept sources are expected to further improve the scan rate; however, not without exacerbating the already severe trade-off in depth range. Here, we show how, without the need for mechanical repositioning, harmonic images can be rapidly synthesized at any depth. This is achieved by opto-electronic modulation of a single-frequency swept source laser in tandem with tailored numerical dispersion compensation. We demonstrate experimentally how real-time imaging of highly-curved samples is enabled by extending the effective depth range 8-fold. Even at the scan speed of a 400 kHz swept source, harmonic OCT enables widefield retinal imaging.

KW - ophthalmology

KW - optical coherence tomography

KW - computational imaging

KW - OCT

KW - healthcare

UR - https://www.scopus.com/pages/publications/85210178416

U2 - 10.1364/BOE.540278

DO - 10.1364/BOE.540278

M3 - Article

C2 - 39553869

SN - 2156-7085

VL - 15

SP - 6573

EP - 6587

JO - Biomedical Optics Express

JF - Biomedical Optics Express

IS - 11

ER -