Powering Organic Flexible Optical Waveguides and Circuits via Focused Micro‐LEDs for Visible Light Communication

The utilization of organic crystals in visible light communication (VLC) technologies necessitates affordable light‐emitting diodes (LEDs) as sources to run photonic devices. A sustainable strategy is demonstrated utilizing a commercial ultravoilet (UV) LED source to power flexible crystal waveguides of ( Z )‐3‐(3′,5′‐bis(trifluoromethyl)‐[1,1′‐biphenyl]‐4‐yl)‐2‐(4‐methoxyphenyl) acrylonitrile (CF 3 OMe), 9,10‐bis(phenylethynyl)anthracene (BPEA), and 2,2′‐((1 E ,1′ E )‐hydrazine‐1,2‐diylidenebis(methaneylylidene))diphenol (SAA), transducing their respective blue, orange, and yellow fluorescence signals. The focused LED's capability includes i) exciting extremely bent crystal waveguides, ii) evanescently exciting SAA waveguide via energy transfer from a CF 3 OMe waveguide, and iii) selectively exciting and splitting various signals using a 2 × 2 hybrid directional coupler based on SAA‐BPEA crystals. These demonstrations underscore the practicality of the proposed technique for sustainable applications in photonic systems related to VLC.