An artistic impression of the nano-optic endoscope utilizing a flat lens (metalens) to enable high-resolution endoscopic imaging at an extended depth-of-focus by avoiding the image distortions of standard lenses. (Credit: Second Bay Studios/Harvard SEAS)

A new class of endoscopic imaging catheters — termed nano-optic endoscopes — overcome the limitations of current systems. The new endoscopes see deep into tissue at high resolution. The use of nano-optic catheters that incorporate metalenses into their design will likely change the landscape of optical catheter design, resulting in a dramatic increase in the quality, resolution, and functionality of endoscopic microscopy. The researchers say this will ultimately increase clinical utility by enabling more sophisticated assessment of cell and tissue microstructure in living patients.

Metalenses based on flat optics are a game-changing new technology because the control of image distortions necessary for high-resolution imaging is straightforward compared to conventional optics, which requires multiple complex shaped lenses.

To demonstrate the imaging quality of the nano-optic endoscope, the researchers imaged fruit flesh, swine and sheep airways, and human lung tissue. The team showed that the nano-optic endoscope can image deep into the tissue with significantly higher resolution than provided by current imaging catheter designs.