Fabrication and Characterization of Dual Functional InGaN LED Arrays as the Optical Transmitter and Receiver for Optical Wireless Communications

IEEE Photonics Journal

Sun-Chien Ko¹  Yi-Chen Lu²  Chia-Lung Tsai²  Tong-Wen Wang³  Sheng Hsiung Chang⁴  Atanu Das⁵ 

[1] Advanced Tech. Research Lab., Telecommunication Lab., Chunghwa Telecom Co., Ltd., Taoyuan, Taiwan;Department of Electronic Engineering and Green Technology Research Center, Chang Gung University, Taoyuan, Taiwan;Department of Electronic Engineering, Feng Chia University, Taichung, Taiwan;Department of Physics, Chung Yuan Christian University, Taoyuan, Taiwan;Zhejiang University, Zhejiang, China;

关键词: InGaN;    LED array;    photodiode;    optical wireless communications;   

DOI  :  10.1109/JPHOT.2021.3069841

来源: DOAJ

【 摘 要 】

The feasibility of using InGaN/GaN multiple-quantum-well light-emitting diode arrays (LED arrays) as photodiodes (PDs) is investigated experimentally in addition to their light emitting function. Two discrete LED arrays are produced from one 4 × 4 LED array with a parallel-connected pixel configuration. Such compact designs are useful for light emission or detection at the transmitting/receiving terminals of optical wireless communication systems. Despite 4 × 2 LED arrays achieving a light output power of 67.4 mW at 250 mA, they exhibit an optical responsivity (detectivity) of 0.183 A/W (1.61 × 10¹² cm Hz^1/2W⁻¹) under ultraviolet light illumination (λ = 380 nm) at zero bias. For 4 × 2 LED arrays, the presence of an appreciable ultraviolet light response, together with a high 3-dB bandwidth (∼8 MHz) for modulated light detection, allowed us to build a 15 Mbit/s directed optical link with these LEDs functioning as both the optical transmitter and the receiver. Finally, the unitary LED array-based optical link is capable of real-time transmission of digital audio signals (data rate = 6 Mbit/s) at a propagation distance of 100 cm in free space even though some of the constituent pixels are inactive for light detection.

【 授权许可】

Unknown