Anti-perturbation high-resolution compressive imaging through flexible fibers via random-phased fiber plates

The inherent sensitivity to perturbations for the multimode fiber (MMF) has become a major obstacle for single MMF-based imaging advancing towards applications. MMF-enabled compressive imaging provides a fundamental and elegant solution by employing the short MMF as the speckle illuminator and the inherently stable single-mode fiber as the remaining flexible part. However, existing schemes hardly achieve high resolution, high transmittance, minimization and robustness at the same time. Here, we propose the random-phased fiber plate to quickly scramble the incident light field to generate speckle patterns with high spatial resolution and low correlation. Cascading such plates forms the cascaded short MMF (CSMMF) to enhance this effect while maintaining the minimal size and high transmittance. By connecting a single-mode multicore fiber (MCF) to the CSMMF, the incident wavelength and position can be variated in a hybrid way to take full advantage of the CSMMF. Experimentally, the superiorities of CSMMF-generated speckles are demonstrated, providing >0.77 structural similarity and >4.81 dB signal-to-noise ratio for reconstructing multi-resolution objects. The high robustness and high image-reconstruction quality for the MCF-CSMMF probe in compressive imaging (at 5% sampling rate) are also testified. This work provides a feasible solution for applicating single MMF-based imaging in stringent conditions.