Acquisition of high-resolution images from within internal organs using endoscopic optical imaging has numerous clinical applications. However, difficulties associated with optical aberrations and the trade-off between transverse resolution and depth of focus significantly limit the scope of applications. Here, we integrate a metalens, with the ability to modify the phase of incident light at subwavelength level, into the design of an endoscopic optical coherence tomography catheter (termed nano-optic endoscope) to achieve near diffraction-limited imaging through negating non-chromatic aberrations. Remarkably, the tailored chromatic dispersion of the metalens in the context of spectral interferometry is utilized to maintain high-resolution imaging beyond the input field Rayleigh range, easing the trade-off between transverse resolution and depth of focus. We demonstrate endoscopic imaging in resected human lung specimens and in sheep airways in vivo. The combination of the superior resolution and higher imaging depth of focus of the nano-optic endoscope is likely to increase the clinical utility of endoscopic optical imaging.

使用内窥镜光学成像从内部器官内获取高分辨率图像具有许多临床应用。然而，与光学像差相关的困难以及横向分辨率和焦深之间的权衡极大地限制了应用范围。在这里，我们将能够在亚波长水平上改变入射光相位的金属元素整合到内窥镜光学相干断层成像导管（称为纳米光学内窥镜）的设计中，从而通过消除非彩色成像来实现近衍射极限成像畸变。值得注意的是，在光谱干涉仪的背景下，量身定制的金属元素色散被用于维持超出输入场瑞利范围的高分辨率成像，减轻横向分辨率和焦点深度之间的权衡。我们展示了切除的人类肺部标本和绵羊气管体内的内窥镜成像。纳米光学内窥镜的优异分辨率和更高成像焦点深度的结合可能会增加内窥镜光学成像的临床效用。