Autonomous vehicles rely on accurate perception of their immediate surroundings. It is necessary to detect the presence of other vehicles, pedestrians, and other relevant obstacles in everyday traffic situations.
The need for accurate ranging and detection in autonomous driving cars has led to the introduction of LiDAR (Ligth Detection and Ranging) systems to complement camera- or radar-based sensors.
Macro-mechanical Scanning LiDAR
Despite the emergence of solid-state LiDAR systems, macro-mechanical scanning LiDARs are still the most technically mature and hence the most widely deployed LiDAR types in Advanced Driving Assistance Systems, Robotic Vehicles, and industrial LiDAR applications. At the heart of a macro-mechanical, scanning LiDAR is a fast rotating or oscillating mirror that with the emitted light from multiple laser diodes scans the surrounding environment.
MEMS Scanning LiDAR
Newer generation LiDARs avoid large moving mirrors to reduce size and costs and mitigate the risk of failure due to fatigue of mechanical parts. A common approach is to replace the spinning mirror of a mechanical LiDAR with tiny fast-scanning MEMS-based mirrors manufactured by semiconductor processes.
Flash LIDAR
Flash LIDAR operation is very similar to that of a camera using an optical flash. In Flash LIDAR, a single laser pulse illuminates the environment in front of the car and an array of photodetectors captures the back-scattered light. The detector captures the distance to an obstacle, its location and reflected intensity.
Since this method captures the entire scene in a single-shot the data is acquired much faster compared to scanning with a rotating mirror.
Materion Optics Balzers has provided key components to the first LiDAR systems ever deployed on the road in series-manufactured cars. We are committed to continue the development of our coating solutions and optical components to make LiDAR a mature and widely-adopted sensor technology in our future cars.
