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arXiv · 2409.01252

Computer-generated holography enables high-uniformity, high-efficiency depth-of-focus extension in endoscopic OCT

Chengfu Gu·Haoran Zhang·Qi Lan·Weiyi Zhang·Chang Liu·Jianlong Yang
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Abstract

Fiber-form optics extends the high-resolution tomographic imaging capabilities of Optical Coherence Tomography (OCT) to the inside of the human body, i.e., endoscopic OCT. However, it still faces challenges due to the trade-off between probe size, resolution, and Depth Of Focus (DOF). Here we introduce a method for extending the DOF in endoscopic OCT with high uniformity and efficiency. On the basis of multi-level diffractive optics, we leverage the multi-dimensional light field modulation capabilities of Computer-Generated Holography (CGH), to achieve precise control of the intensity distribution of the off-axis portion of the OCT probe light. Our method eliminates the need for an objective lens, allowing for direct fabrication at the distal facet of a single-mode fiber using femtosecond laser two-photon 3D printing. The superiority of our method has been verified through numerical simulation, beam measurement, and imaging results obtained with our home-built endoscopic OCT system.

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Chengfu Gu, Haoran Zhang, Qi Lan, Weiyi Zhang, Chang Liu, Jianlong Yang. 2024-09-02. Computer-generated holography enables high-uniformity, high-efficiency depth-of-focus extension in endoscopic OCT. https://arxiv.org/abs/2409.01252

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