Prototype scanning fiber endoscope

Commercial optical endoscopes rely on image transfer and acquisition based on an array of photon detectors, such as a coherent fiberoptic bundle, a video camera, and/or the human retina. An alternative approach uses a resonantly vibrating optical fiber that scans laser illumination. However, the limitation of laser-scanning endoscopic development has been the technological challenge of fabricating a small diameter, opto-mechanical scanner. A proof-of-concept micro-optical scanner has been built using a 2.3 mm diameter piezoelectric actuator and 4 mm diameter lenses. Images are generated using resonant spiral scanning of the fiber, projecting monochromatic laser light to an illumination plane. A single photodetector is used to acquire grayscale images one pixel at a time. In vitro, the acquired images of test targets have 10 to 20 micrometers maximum spatial resolution and a field-of-view that can be electronically varied.