The three main ranging methods of LiDAR are Time of Flight (ToF), Phase, and Triangulation.



The distance measurement principle of Time of Flight (ToF) method is to calculate the distance by measuring the time from emission to return of laser pulses. The LiDAR emits a laser pulse, then detects the time it takes for the laser pulse to reflect back from the target object, and calculates the distance from the LiDAR to the target object based on the speed and time of light. This method has high accuracy, but requires high-precision timers and has certain requirements for the reflection properties of the target.

The distance measurement principle of Phase method is to calculate the distance by measuring the phase difference between laser emission and reception. The LiDAR emits a modulated frequency laser beam, and by measuring the phase difference between the reflected laser and the emitted laser, the distance from the LiDAR to the target object can be calculated. This method has high accuracy, but requires a stable laser source and precise phase measurement equipment.



The distance measurement principle of triangulation is to calculate the distance by the time difference between the laser reflection signal received by the laser and the photoelectric receiver at different positions. The LiDAR emits a beam of laser, which is reflected off the target object and received by a photoelectric receiver. By measuring the angle difference between the emitted and received laser, the distance from the LiDAR to the target object can be calculated. This method requires lower hardware requirements, but the accuracy is also relatively low.



Overall, different ranging methods have their own advantages and disadvantages, and appropriate ranging methods should be selected based on specific application scenarios and needs.