LiDAR 101: How Light Detection And Ranging Systems Work
Many different industries use light detection and ranging systems, also known as LiDAR, to be successful in their operations. Oceanographers use it to gather calculations about the ocean surface and depths, military personnel use it to create high-resolution maps of surrounding borders, and a civil engineering management system can use it to capture coordinates of transportation infrastructure.
As over 25% of bridges in the U.S. are in need of significant repairs or are handling more traffic than they were designed to carry, this technology can help keep traveling citizens safe. Learn exactly how LiDAR technology does all of this and more by knowing the basics of how it operates.
How LiDAR Systems Works
Light detection and ranging systems gather their measurements based on how fast light travels. A LiDAR instrument generates rapid pulses of laser light at a surface. A mounted sensor detects the pulses as they bounce back. As light travels at a constant and known speed, the sensor can calculate the distance between the target and itself with incredibly high accuracy. As the instrument repeatedly fires the light pulses, the sensors can construct a complex map of the target.
In airborne LiDAR, the sensor is mounted on an aircraft or helicopter. As the sensor moves, the height, location, and orientation of the instrument must be notated for proper accuracy. Ground-based LiDAR should also take location into account when the instrument is moved.
Components Of LiDAR Systems
One of the primary parts of light detection and ranging systems are lasers. The lasers in these systems are categorized by their wavelength. Lasers with wavelengths between 600 and 1000nm are more commonly used in non-scientific applications as they are focused and eyes can absorb them. For certain applications, like in the military, eye-safe lasers are extremely important.
To develop images in the system, scanners and optics are used to get the necessary information into the processors. Different scanning methods are used for different methods, such as dual oscillating plant mirrors, polygonal mirrors, and dual axis scanners. The optic type determines the resolution and range that a system is able to detect. A photodetector is a device that can read and record LiDAR signals that are returned to the system.
Modern civil engineering and environmental research would not be what it is without the use of LiDAR systems. These high-tech systems are essential in capturing natural data that is otherwise hard to measure.