We demonstrate the application of deep learning for the identification of particles, directly from their backscattered light. The particles were illuminated using a single-mode fibre-coupled laser light source and the scattered light was collected by a 30-core optical fibre. The technique enabled identification of the specific species of pollen grains with an accuracy of ~97%, even in the presence of high levels of background light equivalent to daytime sunlight. In addition, the technique determined the distance between the fibre tip and the particles with an accuracy of ± 6 µm.
Space division multiplexing (SDM) utilizing few-mode fibers or multicore fibers supporting multiple spatial channels, is currently under intense investigation as an efficient approach to overcome the current capacity limit of high-speed long-haul transmission systems based on single mode optical fibers. In order to realize the potential energy and cost savings offered by SDM systems, the individual spatial channels should be simultaneously multiplexed, transmitted, amplified and switched with associated SDM components and subsystems. In this paper, recent progress on the implementation of various SDM amplifiers and its related SDM components is presented.
A novel approach of using multi-element fiber (MEF) technology in space-division multiplexing (SDM) systems is presented. This paper reviews the progress in fabrication and characterization of MEF based both ultralow crosstalk transmission and amplifier fibers. Passive 3-element MEFs have been successfully demonstrated for application in telecommunications. An active 5-element MEF amplifier has also been demonstrated in a novel multiport cladding-pumped configuration, in which a central un-doped multi-mode pump fiber-element is surrounded by four Er/Yb-doped active fiber-elements. MEF is compatible with current WDM systems, and there is no need to develop specialized multiplexing/demultiplexing components. Moreover, it offers a smooth upgrade to SDM systems.