Coaxial transceiving LiDAR based on a silicon photonic optical phased array.

Area of Science:

• Photonics and Optical Engineering
• LiDAR Technology
• Integrated Optics

Background:

• High-performance light detection and ranging (LiDAR) systems require advanced optical phased arrays (OPAs) and frequency-modulated continuous-wave (FMCW) technology.
• Existing LiDAR systems often necessitate bulky off-chip components like circulators and collimators, increasing system complexity and size.

Purpose of the Study:

• To propose and experimentally demonstrate a compact coaxial transceiver for LiDAR systems utilizing a single OPA.
• To simplify the fabrication of long optical grating antennas by leveraging bound states in the continuum.
• To integrate FMCW technology for precise ranging measurements within the developed LiDAR system.

Main Methods:

• Development of a silicon-on-insulator (SOI) platform for fabricating the OPA.
• Utilization of bound states in the continuum to enable single-step etching for long grating antennas.
• Experimental demonstration of a coaxial transceiver architecture integrating a single OPA and FMCW ranging.

Main Results:

• Achieved a vertical beam divergence of 0.076° with a 1.5 mm long grating antenna.
• Measured a wide field of view (FOV) of 40° × 8° without grating lobes across a 60 nm wavelength band.
• Successfully demonstrated FMCW ranging measurements at various angles using the single OPA coaxial transceiver.

Conclusions:

• The proposed single OPA coaxial transceiver design significantly simplifies LiDAR systems by eliminating the need for off-chip circulators and collimators.
• The integration of bound states in the continuum offers a more efficient and precise method for fabricating optical grating antennas.
• The demonstrated system paves the way for more compact, high-performance, and cost-effective LiDAR solutions for various applications.