What is LiDAR?
Light Detection and Ranging (LIDAR) is a technology that utilizes lasers to determine the distance to an object or surface. It is used in a variety of industries, including atmospheric physics, geology, forestry, oceanography, and law enforcement. LIDAR is similar to radar, but it incorporates laser pulses rather than sound waves. Both systems determine distance by measuring the time delay between transmission and reflection of a pulse. For many applications, LIDAR is a better choice than radar, because it has a greater ability to reflect images, making more objects visible. When using data collection systems that involve aiming wavelengths at a target and waiting for a reflection, it is usually only possible to collect information for objects the same size as the wavelength or longer. LIDAR uses waves ten to one hundred thousand times shorter than radar waves, meaning that it is able to collect much more data. A basic LIDAR system includes a transmitting laser and receiver, and LIDAR
Light Detection and Ranging (LIDAR) is a technology similar to RADAR that can be used to create high-resolution digital elevation models (DEMs) with vertical accuracy as good as 10 cm. LIDAR equipment, which includes a laser scanner, a Global Positioning System (GPS), and an Inertial Navigation System (INS), is generally mounted on a small aircraft. The laser scanner transmits brief laser pulses to the ground surface, from which they are reflected or scattered back to the laser scanner. Detecting the returning pulses, the equipment records the time that it took for them to go from the laser scanner to the ground and back. The distance between the laser scanner and the ground is then calculated based on the speed of light. While flying, the airplanes position is determined using GPS, and the direction of the laser pulses are determined using the INS. Because one laser pulse may reflect back from multiple surfaces, such as the top of a tree, a house, and the ground surface, there are mul
LIDAR is actually an acronym for “LIght Detection And Ranging”. It can be thought of as a laser radar. Radar utilizes radio waves to make its measurements, as opposed to LIDAR which uses laser light. A basic LIDAR instrument is made up of a laser source, telescope, and detection system. A laser pulse is emitted into the atmosphere, scatters from the air molecules and aerosols (particulate in the air such as dust) and returns through the telescope system. The detection system collects the light, and analyzes the data to determine the wind velocity, air temperature, and air density (air pressure is derived from the temperature and density).
