Nonlinear vibration-enhanced fiber-optic MEMS scanner and shape memory polymer catheter for potential microscopy application

This study presents a novel endoscopic device that addresses key limitations in current systems by integrating a fiber-optic piezoelectric MEMS hybrid scanner with a shape memory polymer (SMP) catheter. The MEMS scanner uses aerosoljetted PZT bimorph push-pull actuators and nonlinear vibration to generate controlled circular and spiral scan patterns, enabling high-resolution imaging and an enhanced field of view (FOV). A tapered optical fiber reduces scattering and facilitates independent 2-axis scanning, improving imaging performance. The newly developed SMP catheter offers exceptional flexibility for navigating complex anatomical structures, with programmable multi-stage movements that enhance maneuverability. Experimental validation demonstrates a 60 μm spiral scan area at a 10 Hz frame rate, successfully reconstructing fine details such as 5 μm lines and Psychodidae wing structures. The inclusion of the SMP catheter provides exceptional flexibility for navigating complex anatomical structures. Its ability to bend, twist, and stretch (e.g., 360° bend, 540° twist, and 30% extension) with programmable multi-stage movements enhances both FOV and maneuverability, making it an ideal tool for endoscopic applications. The system's versatility is further highlighted by its integration with micro-display technology using a field-programmable gate array (FPGA), significantly improving diagnostic accuracy and efficiency.