LIDAR is Light detection and Ranging is a sensor used for measuring distance using pulsed laser(LASER: Light Amplification from Stimulated emission of Radiation). It is an active sensor as it has it’s own laser source and it enables it to collect data even in low or no light.
LIDAR is very accurate and is widely used by companies involved in developing technology for autonomous diving. The basic principle consists of firing a laser and measuring the distance by calculating the TOF(Time of Flight) from the bounced laser.
The LIDAR is now modified with spinning heads which makes it possible to obtain data from all directions. LIDAR scans in a single plane, so the data is 2D(two dimentional). 3D LIDAR is also avilable which scans the environment in 3 Dimentional and hence the data obtained is highly useful.