Laser - Radar
Figure 1: LIDAR from SCHOTT North America, Inc.
(see Video on https://microsites.schott.com/us-lidar/english/index.html)
Laser - Radar
Laser - Radars are radars that operate in the optical wavelength range
(including ultraviolet and infrared) and use lasers as a radiation source.
Common abbreviations for Laser - Radars are
- Ladar (Laser - Radar) and
- Lidar (Light Detecting and Ranging),
whereby the latter designation is increasingly gaining acceptance in the civil sector.
Similar to conventional radar, the measuring principle of lidar is based on the emission of short light pulses into the atmosphere. The light scattered back into the measuring system by a detected object is then collected by a telescope and detected, for example, by a photodiode or a photomultiplier.
Due to the wavelengths which are typically certain magnitudes shorter than those of millimeter-wave radars, with lidars can be achieved a much better range resolution.
The distance information is contained in the transit time of the laser pulse and thus in the time course of the reflected or backscattered signal. Spatial representation is also possible by successive measurements in many different, closely spaced directions. Speed measurements are already being carried out using the Doppler method in the laser-based speed gauges used for traffic control.