Research on the Control Technology of Optical Phased Array High-Speed Scanning

An optical phased array (OPA) is a suitable device for producing emission beams in LiDAR. In order to achieve high-speed scanning control of the output beam by OPA chips, we designed and produced a 128-channel silicon-based OPA chip based on electrooptic modulation. Considering the characteristics of multiphase control in electrooptic OPA chips, a parallel dual-port random access memory (RAM) inside a field programmable gate array (FPGA) technology is used to achieve optical phase control for each channel. The entire system is implemented by existing FPGA chips and digital-to-analog converters (DACs). To implement the circuit system, we also built a high-speed testing environment for OPA scanning. The system was used to verify the main performance of our designed OPA chip and achieve high-speed scanning control. The test results show that our designed OPA chip and control circuit can achieve fast scanning of the emission beam. The optical phase configuration time is less than
$5~\mu $
s. This system can meet the requirements of fast scanning control for all solid-state LiDAR optical emission modules. This work lays the foundation for our subsequent development of an OPA-based all solid-state LiDAR prototype.