How does lidar work?
LIDAR, which stands for light detection and ranging, has become a common fixture on self-driving cars operated by companies like GM and Alphabet’s Waymo. But Musk has long argued that LIDAR is too expensive and too bulky for Tesla’s vehicles.
lidar works much like radar, but instead of sending out radio waves it emits pulses of infrared light—aka lasers invisible to the human eye—and measures how long they take to come back after hitting nearby objects. It does these millions of times a second, then compiles the results into a so-called point cloud, which works like a 3-D map of the world in real time—a map so detailed it can be used not just to spot objects but to identify them. Once it can identify objects, the car’s computer can predict how they will behave, and thus how it should drive.