Fluorescent Concentrators/Antennas in Optical Wireless Communication

Optical wireless communication (OWC) is expected to play a crucial role in future wireless communication networks due to its several advantages, including a license-free spectrum, robustness to electromagnetic interference, and ultra-wide bandwidth that enables very high transmission data rates. In most OWC systems, the received light typically requires amplification in the optical domain using lenses or compound parabolic collectors (CPCs). However, these approaches are constrained by the conservation of étendue, which results in a limited field of view (FOV) of the optical receiver.

Recent studies have shown that fluorescent concentrators/antennas can effectively concentrate light without being limited by étendue. Since the concentration principle of these antennas is based on fluorescence, they can achieve both high concentration gain and a wide FOV. Nevertheless, the photoluminescence (PL) lifetime of these antennas introduces an additional bandwidth-limiting factor. Fortunately, advancements in materials science techniques have significantly reduced the PL lifetime to just a few nanoseconds or even lower, thereby supporting the transmission of data at a high rate . This talk reviews the recent trend of exploring new fluorescent concentrators in various OWC applications, including visible light communications (VLCs) and underwater OWCs. These concentrators include those made from commercially available fluorescent fibers, as well as organic and inorganic fluorescent materials.