Sensing close up distances has mostly been the domain of sonar, partly because of it’s low cost and limitations do do much larger distance. Larger distances have been the domain of LIDAR, which can be scaled to do inches to miles, however it’s higher costs and larger sizes limit the use for small and cheap applications.
Researchers at MIT’s Photonic Microsystems Group have developed a lidar-on-a-chip system that can be mass produced cheaply. Practical applications include self-driving cars, drones, and robots.
Most lidar systems—like the ones commonly seen on autonomous vehicles—use discrete free-space optical components like lasers, lenses, and external receivers. In order to have a useful field of view, this laser/receiver module is mechanically spun around, often while being oscillated up and down. This mechanical apparatus limits the scan rate of the lidar system while increasing both size and complexity, leading to concerns about long-term reliability, especially in harsh environments. Today, commercially available high-end lidar systems can range from $1,000 to upwards of $70,000, which can limit their applications where cost must be minimized.
Many new cars have sonar based detection in the bumpers for detecting obstructions, cross traffic, and pre-impact, however these systems have range limitations. A LIDAR based system should be lower cost in mass production, and produce a longer range and more reliable result, with a greater degree of information from the sensor. It would be possible to detect the shape of an object and direction of the object.
On-chip lidar systems could even be placed in the fingers of a robot, allowing it to see what it is grasping. These developments have the potential to dramatically alter the landscape of lidar systems by changing how the devices operate and opening up the technology to numerous new applications.