www.eetimes.eu, Mar. 25, 2021 –
The LiDAR sets the scene in 3D, which makes it a valuable technology for future sensing and vision systems. Its high cost, however, remains a major obstacle to mass integration. Leveraging silicon photonics, CEA-Leti has been working on Optical Phased Arrays (OPAs) to produce cost-effective and compact LiDARs.
In an interview with EE Times Europe, CEA-Leti's researchers Sylvain Guerber and Daivid Fowler explained the development, calibration and characterization steps of silicon photonics OPAs for LiDARs. CEA-Leti has indeed developed genetic algorithms to calibrate high-channel-count OPAs and a measurement setup compatible with wafer-scale OPA characterization.
OPA-based LiDARs
A LiDAR is a remote sensing method that calculates the time it takes for a beam of light to strike an object or surface and reflect back to the laser scanner. Traditional LiDAR systems are made of discrete components whose mechanical assembly makes them fragile, expensive, and cumbersome. Using a photonic chip, CEA-Leti claims the current optical beam scanning system (moving mirrors) can be replaced by an integrated OPA (no moving mechanical parts). The cost and size of the LiDAR are significantly reduced while its performance (e.g. scanning speed, power efficiency, resolution...) is improved thanks to solid-state beam steering.