ToF camera uses Time of Flight for distance measurement. In theory, there are two types of ToF cameras: single-point ranging and multi-point ranging. Single-point ranging is the distance that can only measure one point at a time. Use laser + galvanometer to illuminate a certain point of the object, and then use photodiode (PIN) or avalanche diode (APD) to measure the light back and forth time and distance. The laser continuously scans the object + the photosensitive tube continuously measures the distance, and the 3D image of the object can be obtained. Single-point ranging is divided into pulse type and phase type according to the method of measuring time. The former has fast measurement speed and average accuracy, while the latter has the opposite characteristics. At present, the lidar for auto-driving cars is based on single-point ranging (the essence of solid-state phase-controlled radar is also single-point ranging), which is characterized by long effective distance. Equipment based on multi-point ranging basically uses tof camera.
All-Time-of-Flight (ToF) camera measure distances using the time that it takes for photons to travel between two points, from the sensor's emitter to a target and then back to the sensor's receiver. Indirect and direct ToF both offer specific advantages in specific contexts.
