How a laser rangefinder works
Laser rangefinders generally use two methods to measure distance: the pulse method and the phase method.
The process of pulse method ranging is that the laser emitted by the range finder is reflected by the object to be measured and then received by the range finder, and the range finder records the time of the laser round trip at the same time. Half the product of the speed of light and the round-trip time is the distance between the rangefinder and the object being measured. The accuracy of the distance measurement by the pulse method is generally about +/- 1 meter. In addition, the measurement blind area of this type of rangefinder is generally about 15 meters.
The phase laser rangefinder uses the frequency of the radio band to modulate the amplitude of the laser beam and measure the phase delay generated by the modulation light going back and forth to the measuring line, and then convert the distance represented by the phase delay according to the wavelength of the modulated light. That is, the time required for the light to travel back and forth through the survey line is measured by an indirect method.
