Development and characterization of a clinically viable metalens-enhanced optical endoscope.

Metalens technology has been shown to offer significant enhancement and versatility over traditional lenses in endoscopic optical coherence tomography, but only in proof-of-principle form ultimately unsuitable for clinical imaging. In this work, we present, to the best of our knowledge, the first clinically viable metalens-enhanced optical endoscope, using novel processing techniques to fabricate the metalens directly onto the surface of a 500 μm prism. Taking full advantage of the precision beam shaping offered by metasurface technology, we have incorporated astigmatism correction and beam tilting into the metalens design itself, improving optical performance while simultaneously reducing complexity in the optical assembly. We characterize our assembled endoscope through both beam characterization and biological imaging, the latter of which we compare against a ball lens design. These results demonstrate a metalens endoscope with improved optical performance that is fully capable of replacing traditional designs.