Liquid-shaped microlens for scalable production of ultrahigh-resolution OCT microendoscope

TL;DR

This paper presents a scalable liquid shaping method for fabricating ultrathin, high-performance OCT microendoscopes with customizable freeform microlenses, enabling ultrahigh-resolution imaging of internal organs in small animals.

Contribution

A novel liquid shaping technique for rapid, scalable production of ultrathin OCT microendoscopes with customizable freeform microlenses for minimally invasive imaging.

Findings

Fabricated 800-nm OCT microendoscopes with 0.6 mm diameter

Achieved ultrahigh-resolution imaging in rat esophagus and mouse aorta and brain

Demonstrated the technique's scalability and customization capabilities

Abstract

Endoscopic optical coherence tomography (OCT) is a valuable tool for providing diagnostic images of internal organs and guiding interventions in real time. Miniaturized OCT endoscopes are essential for imaging small and convoluted luminal organs while minimizing invasiveness. However, current methods for fabricating miniature fiber probes have limited ability to correct optical aberrations, leading to suboptimal imaging performance. In this study, we introduce a new paradigm of liquid shaping technique for the rapid and scalable fabrication of ultrathin and high-performance OCT microendoscopes suitable for minimally invasive clinical applications. This technique enables the flexible customization of freeform microlenses with sub-nanometer optical surface roughness by regulating the minimum energy state of curable optical liquid on a wettability-modified substrate and precisely controlling the liquid volume and physical boundary on a substrate. Using this technique, we simultaneously fabricated 800-nm OCT microendoscopes with a diameter of approximately 0.6 mm and evaluated their ultrahigh-resolution imaging performance in the esophagus of rats and the aorta and brain of mice.