An ultra-thin multimode fiber is an ideal platform for minimally invasive microscopy with the advantages of a high density of modes, high spatial resolution, and a compact size. In practical applications, the probe needs to be long and flexible, which unfortunately destroys the imaging capabilities of a multimode fiber. In this work, we propose and experimentally demonstrate sub-diffraction imaging through a flexible probe based on a unique multicore-multimode fiber. A multicore part consists of 120 Fermat’s spiral distributed single-mode cores. Each of the cores offers stable light delivery to the multimode part, which provides optimal structured light illumination for sub-diffraction imaging. As a result, perturbation-resilient fast sub-diffraction fiber imaging by computational compressive sensing is demonstrated.

Dutch Ministry of Economic Affairs, TKI
Opt. Express
Nanoscale Imaging and Metrology

Lyu, Z., Abrashitova, K., de Boer, J., Andresen, E., Hervé, R., & Amitonova, L. (2023). Sub-diffraction computational imaging via a flexible multicore-multimode fiber. Opt. Express, 31(7), 11249–11260. doi:10.1364/oe.481052