LIDAR – sometimes called time of flight (ToF), laser scanners or laser radar – is a sensing method that detects objects and maps their distances. The technology works by illuminating a target with an optical pulse and measuring the characteristics of the reflected return signal. The width of the optical pulse can range from a few nanoseconds to several microseconds.

Figure 1 shows the basic principle of LIDAR, with light shining out in certain patterns and information extracted based on the reflections gathered at the receiving end. Pulse power, round-trip time, phase shift and pulse width are common parameters used to extract information from light signals.

Why choose light? What differentiates LIDAR from other existing technologies such as radar, ultra sonic sensors or cameras? What’s driving the hype around LIDAR? This white paper addresses these questions in the context of long-range LIDAR, which is going to be an important sensor for autonomous driving. In addition to autonomous vehicles, LIDAR has applications in 3D aerial and geographic mapping, safety systems in factories,smart ammunition and gas analysis.