Submillimeter Large High-speed Photodetector for High Optical Alignment Robustness Optical Wireless Communications

We present a submillimeter large high-speed photodetector for mitigating optical alignment issues and low-cost receiver design for free-space optical (FSO) communications. In a 10-m FSO communication demonstration, a high data rate of up to 20-Gbps could be successfully achieved with a 4-mm alignment tolerance.