Compared with binocular vision and structured light solutions, the ToF solution is relatively simple to implement, mainly including the transmitter and receiver.ToF sensor sends a modulation signal to the light source driver chip, and the modulation signal controls the laser to emit high-frequency modulated near-infrared light. After encountering the diffuse reflection of the object, the receiving end calculates the depth information through the phase difference or time difference between the emitted light and the received light. At present, most ToF sensors use back-illuminated CMOS process technology. This process greatly increases the photosensitive area, improves the photon collection rate and the speed of ranging, and the response time can reach ns level, which can also ensure high precision in long distances.
The accuracy of ToF sensor depends on its pulse duration. Compared with binocular vision and structured light schemes, ToF sensor accuracy does not decrease significantly with distance. d-ToF is a key technology for long-distance applications.
