posted on 2025-04-08, 16:05authored byAnnada
Sankar Sadhu, Li-Yin Chen, Yi-Hua Pai, Chung-An Hsieh, Hao-Wu Lin, Chi-Wai Chow, Hao-Chung Kuo
Visible light communication (VLC) represents a forefront
technology
that integrates illumination and data transmission using light-emitting
diodes (LEDs). However, conventional phosphor-based LEDs are limited
by their narrow bandwidth due to slow photoluminescence (PL) lifetimes
and resistive-capacitive (RC) delays, hindering their data transmission
capabilities. In this study, we address these limitations by incorporating
a highly emissive fluorescent organic green emitter, CC-MP4, which
achieves a modulation bandwidth of 185 MHzapproximately 35
times greater than that of traditional phosphors. A commercial orange-red
emitter, MEH-PPV, is also employed as a color-conversion material
in the VLC system. The Förster resonance energy transfer from
CC-MP4 to MEH-PPV decreases the PL lifetimes in the composite blend.
When excited by a semipolar (20–21) blue micro-LED with a bandwidth
of 1233 MHz, the composite system forms a high-bandwidth white-light
source with a correlated color temperature (CCT) of 5249 K, a color
rendering index (CRI) of ∼90, and a total bandwidth of 1027
MHz. This white-light system successfully achieves a data rate of
1.62 Gbps using nonreturn-to-zero on–off keying (NRZ-OOK) modulation.
Notably, the stability of the CC-MP4 film is confirmed after three
months of storage, maintaining robust optical and frequency response
performance, which underscores its potential for practical applications
in VLC and solid-state lighting (SSL).