Photoacoustic endoscopy using polymer microring resonators

Abstract

We designed and fabricated a probe for endoscopic photoacoustic imaging with a structure that includes an optical fiber to deliver laser pulses and polymer microring resonators on transparent fused silica substrate. To calibrate the performance of the probe, a 6 μm carbon fiber embedded in an agarose gel phantom was imaged. At a depth of 2.7 mm from the probe edge, radial resolution up to 21 μm and transverse resolution of 750 μm were obtained. Transverse resolution can be improved using fibers with small core sizes. Experimental results show that the devised probe has potential for high-resolution photoacoustic endoscopy.