Ultra-Thin Optical Sheets for Parallel Data Transmission of Visible Light Communications

Visible light communications (VLCs) have become an important and promising supplement to the Wi-Fi network for the coming 5G communications. Photodetectors with narrow field-of-view are essential for parallel data transmission, such as optical attocell networks and spatial multiple-input and multiple-output arrays. Here, we propose a design of sub-millimeter-scale flexible optical sheets with strong angular selectivity. They can be mounted to any photodetectors even with irregular surfaces and significantly narrow the field-of-view (down to 4ř or less) with a plug-and-play feature. These optical sheets pave the way toward unprecedented progress in cell densification and channel capacity for VLC-based 5G networks.