Laser rangefinder is a very advanced economical online position detection system with amazing test accuracy and excellent stability. Because it emits a laser beam to the target object and uses the reflected beam to accurately calculate the distance, it can reach a very long detection distance without adding a reflective target. Moreover, the size and area of the target object are much smaller than the area required by ultrasonic waves, making it possible to detect the position of small-sized objects at a long distance.
The methods commonly used by laser rangefinders are as follows:
Method 1: Phase laser rangefinder
The phase laser rangefinder uses the frequency of the radio band to modulate the laser beam and measure the phase delay caused by the modulated light going back and forth on the measurement line once, and then converts the distance represented by this phase delay according to the wavelength of the modulated light. That is, it uses an indirect method to measure the time required for the light to go back and forth on the measurement line.
Method 2: Pulse laser ranging
Pulse laser ranging is simply to measure the distance based on the flight time difference of the laser. It uses the characteristics of extremely short laser pulse duration, relatively concentrated energy in time, and large instantaneous power to measure the distance. When there is a cooperative target, it can reach a very long range; in close-range measurement (within a few thousand meters), even if there is no cooperative target, it can also measure the distance when the accuracy requirement is not high. This method is mainly used for terrain measurement, tactical frontier ranging, missile orbit tracking, laser radar ranging, and artificial satellite, Earth-Moon distance measurement, etc.
Method 3: Triangulation laser distance measurement
The measurement method of laser displacement sensor is called laser triangulation reflection method. The accuracy of laser distance meter is certain. The same distance meter has the same accuracy when measuring 10 meters and 100 meters. The measurement accuracy of laser triangulation reflection method is related to the range. The larger the range, the lower the accuracy.
Method 4: Laser echo method
Laser distance measuring detectors use the principle of echo analysis to measure distance and can achieve a certain degree of accuracy. The sensor is composed of a processor unit, an echo processing unit, a laser transmitter, a laser receiver, etc. The laser displacement sensor transmits one million pulses per second to the detection object through the laser transmitter and returns to the receiver. The processor calculates the time required for the laser pulse to encounter the detection object and return to the receiver, and calculates the distance value. The output value is the average output of thousands of measurement results.