What method does LIDAR commonly use to measure distances?

LIDAR, or Light Detection and Ranging, measures distances by using the time delay between the emission of laser pulses and their reception after reflecting off a target. This method involves sending out a pulse of laser light and determining how long it takes for the light to return after hitting an object.

The distance to the target can be calculated using the speed of light as a constant multiplier for the time it takes for the light to travel to the object and back. By measuring this time delay, LIDAR systems can provide highly accurate distance measurements, which are critical for applications such as topographical surveying, forestry management, and autonomous vehicle navigation.

The other methods listed, such as frequency modulation, changes in wavelength, and triangulation techniques, do not directly relate to how LIDAR measures distance. Frequency modulation involves altering the frequency of the laser or signal but is not used for measuring distances in LIDAR. Change in wavelength pertains to spectroscopic techniques rather than direct distance measurement. Triangulation techniques, while used in some ranging systems, are not the primary method for LIDAR, which relies specifically on the speed of light and time-of-flight measurements to determine distances.