Laser Rangefinder | Working Principle of Laser Distance Sensors

Laser rangefinders, also called laser distance sensors, measure distances by projecting a laser beam and detecting the return. Their principle is based on measuring the time of flight or phase change of the laser beam.

Common methods:

- Time-of-flight: emit a short pulse and measure the round-trip time of the reflected light; distance = (time × speed of light) / 2.

- Phase-shift: measure phase differences between emitted and received continuous waves; use interferometric techniques to compute distance.

Laser rangefinders include detectors and timing electronics to capture and process reflected signals. They provide high accuracy, non-contact measurement, and fast response, suitable for surveying, industrial positioning, and motion measurement.