Demonstration of a blue light transmitter with 100Mbps rate, 80° divergence angle, and 18mW optical power for underwater wireless optical communication based on laser diode and engineered diffuser

Underwater wireless optical communication (UWOC) with blue-green light is a useful way to transmit data in ocean for short distance application, because it has high speed. In application, the transmitter should have larger divergence angle to make it easier to establish communication link, besides high modulated rate. Laser diode (LD) is suitable to design such transmitter, thanks to its simpler structure and much faster switching speed. However, it is difficult to be widespread used in ocean engineering because of its quite small divergence angle. For this, we present a transmitter based on blue LD and engineered diffuser. It has 100Mbps modulation rate, 80° divergence angle, and 18mW optical power. It could be used to transmit large volume data in short distance underwater communication.