A multimode fiber endoscopy utilizing fluorescence-based real-valued intensity transmission matrix (RVITM)

A new multimode fiber micro-endoscopy that integrates fiber calibration and imaging phase is proposed. The approach utilizes the back-scattered patterns emitted by the fluorescence targets at the fiber distal end to reconstruct the reflection matrix by phase retrieval algorithm. Simulations show that selective focusing through the fiber is directly achieved using the eigenvectors decomposed from the reflection matrix. It is possible to reconstruct the full fluorescent objects based on speckle correlations. Further experiments will be conducted to explore the focusing and imaging performance. The fluorescence-based reflection matrix method has the potential for re-calibration in situ and robust imaging under moderate perturbations, promising for practical micro-endoscopic applications.