- LiDAR, which stands for Light Detection and Ranging, is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth.
- These light pulses—combined with other data recorded by the airborne system — generate precise, three-dimensional information about the shape of the Earth and its surface characteristics.
- There are three primary components of a LiDAR instrument — the scanner, laser and GPS receiver.
- Airplanes and helicopters are the most commonly used platforms for acquiring lidar data over broad areas.
- Two types of lidar:
- Topographic lidar: It typically uses a near-infrared laser to map the land.
- Bathymetric lidar: It uses water-penetrating green light to also measure seafloor and riverbed elevations.
How does LiDAR works?
- A LiDAR system measures the time it takes for emitted light to travel to the ground and back.
- That time is used to calculate the distance travelled.
- Distance travelled is then converted to elevation.
Applications of LiDAR
- Lidar systems allow scientists and mapping professionals to examine both natural and manmade environments with accuracy, precision, and flexibility.
- It is used to produce more accurate shoreline maps, make digital elevation models for use in geographic information systems, assist in emergency response operations, and in many other applications.
What is Remote Sensing?
- Remote sensing is the science of obtaining information about objects or areas from a distance, typically from aircraft or satellites.
- Remote sensors can be either passive or active.
- Passive sensors respond to external stimuli. They record natural energy that is reflected or emitted from the Earth's surface. The most common source of radiation detected by passive sensors is reflected sunlight.
- Active sensors use internal stimuli to collect data about Earth. For example, a laser-beam remote sensing system projects a laser onto the surface of Earth and measures the time that it takes for the laser to reflect back to its sensor.
Q) What is Remote Sensing?
Remote sensing is the science of obtaining information about objects or areas from a distance, typically from aircraft or satellites.Remote sensors can be either passive or active.