Microendoscopes are vital for disease detection and clinical diagnosis. The essential issue for microendoscopes is to achieve minimally invasive and high-resolution observations of soft tissue structures inside deep body cavities. Obviously, the microscope objective is a must with the capabilities of both high lateral resolution in a wide field of view (FOV) and miniaturization in size. Here, we propose a meta-objective, i.e., microscope objective based on cascaded metalenses. The two metalenses, with the optical diameters of 400 μm and 180 μm, respectively, are mounted on both sides of a 500-μm-thick silica film. Sub-micrometer lateral resolution reaches as high as 775 nm in such a naked meta-objective, with monochromatic aberration correction in a 125 μm full FOV and near diffraction limit imaging. Combined with a fiber bundle microscope system, the single cell contour of biological tissue (e.g., water lily leaf) can be clearly observed, compared to the indistinguishable features in other conventional lens-based fiber bundle systems, such as plano–convex and gradient refractive index (GRIN) cases.

中文翻译：

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微型内窥镜具有亚微米分辨率的元物镜

微型内窥镜对于疾病检测和临床诊断至关重要。微型内窥镜的基本问题是实现对深体腔内软组织结构的微创和高分辨率观察。显然，显微镜物镜是必需的，具有在宽视场（FOV）中具有高横向分辨率和在尺寸上小型化的能力。在这里，我们提出了一个元物镜，即基于级联金属镜的显微镜物镜。光学直径分别为400μm和180μm的两个metalense安装在500μm厚的二氧化硅膜的两侧。在这样一个赤裸的亚物镜中，亚微米的横向分辨率高达775 nm，在125μm的全视场和近衍射极限成像中具有单色像差校正。结合纤维束显微镜系统，