  Endoscopes are an important component for the development of minimally
invasive surgeries. Their size is one of the most critical aspects, because
smaller and less rigid endoscopes enable higher agility, facilitate larger
accessibility, and induce less stress on the surrounding tissue. In all
existing endoscopes, the size of the optics poses a major limitation in
miniaturization of the imaging system. Not only is making small optics
difficult, but their performance also degrades with downscaling. Meta-optics
have recently emerged as a promising candidate to drastically miniaturize
optics while achieving similar functionalities with significantly reduced size.
Herein, we report an inverse-designed meta-optic, which combined with a
coherent fiber bundle enables a 33% reduction in the rigid tip length over
traditional gradient-index (GRIN) lenses. We use the meta-optic fiber endoscope
(MOFIE) to demonstrate real-time video capture in full visible color, the
spatial resolution of which is primarily limited by the fiber itself. Our work
shows the potential of meta-optics for integration and miniaturization of
biomedical devices towards minimally invasive surgery.
