Supercontinuum sources for optical coherence tomography (OCT) have raised great interest as they provide broad bandwidth to enable high resolution and high power to improve imaging sensitivity. Commercial fiber-based supercontinuum systems require high pump powers to generate broad bandwidth and customized optical filters to shape/attenuate the spectra. They also have limited sensitivity and depth performance. We introduce a supercontinuum platform based on a 1-mm² Si₃N₄ photonic chip for OCT. We directly pump and efficiently generate supercontinuum near 1300 nm without any postfiltering. With a 25-pJ pump pulse, we generate a broadband spectrum with a flat 3-dB bandwidth of 105 nm. Integrating the chip into a spectral domain OCT system, we achieve 105-dB sensitivity and 1.81-mm 6-dB sensitivity roll-off with 300-μW optical power on sample. We image breast tissue to demonstrate strong imaging performance. Our chip will pave the way toward portable OCT and incorporating integrated photonics into optical imaging technologies.

中文翻译：

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用于光学相干断层扫描的毫米级芯片超连续谱生成

用于光学相干断层扫描 (OCT) 的超连续谱源引起了极大的兴趣，因为它们提供了宽带宽以实现高分辨率和高功率以提高成像灵敏度。商用基于光纤的超连续谱系统需要高泵浦功率来产生宽带宽和定制的滤光片来整形/衰减光谱。它们的灵敏度和深度性能也有限。我们介绍了一个基于 1-mm ² Si ₃ N _{4的超连续谱平台}用于 OCT 的光子芯片。我们直接泵浦并有效地产生接近 1300 nm 的超连续谱，无需任何后过滤。使用 25-pJ 泵浦脉冲，我们生成了具有 105 nm 平坦 3-dB 带宽的宽带频谱。将芯片集成到光谱域 OCT 系统中，我们实现了 105-dB 灵敏度和 1.81-mm 6-dB 灵敏度滚降，样品上的光功率为 300-μW。我们对乳房组织进行成像以展示强大的成像性能。我们的芯片将为便携式 OCT 和将集成光子学融入光学成像技术铺平道路。