Abstract: An optical fiber splice tray for connecting a solid core optical fiber (SMF) with a hollow core optical fiber (HCF) is disclosed. The tray may include a body, a first holder, a second holder, and one or more fiber-routing features. The first and second holders may be disposed on the body and configured to hold and secure one or more optical components. The fiber-routing features may be disposed on the body and configured to hold and route one or more HCFs or one or more SMFs within the fiber tray.

Abstract: A coupler for connecting a single mode fiber (SMF) and a hollow core fiber (HCF) is disclosed. The coupler may include an SMF portion, an HCF portion and a graded index fiber (GRIN) portion. The GRIN portion may be disposed between the SMF portion and the HCF portion. One end of the GRIN portion may touch the SMF portion, and the other end of the GRIN portion that faces the HCF portion may be engineered to reduce back-reflection.

Abstract: A system and method for measuring the optical phase of incident light using direct detection and for producing speckle-free images, designed for use with coherent illumination and reflective imaging geometries. Applications include speckle mitigation for active imaging, resolution enhancement using synthetic aperture methods, and digitally correcting aberrations in images or refocusing. The system hardware combines pupil-plane phase modulation with dual-plane direct-detection measurements of the image and pupil-plane intensities. The reconstruction software uses a regularized-inversion estimation framework that couples a data-fidelity model, a physics-based model for rough surface scattering of coherent light, and convolutional neural network model for natural images. The regularized inversion framework is solved iteratively using alternating projection.