The difference between ToF and structured light technology in the application of AR/VR devices

ToF technology maintains relatively stable precision at medium and long distances (generally above 2 meters), although the absolute precision may be as good as that of structured light at short distances, its advantages in long-distance measurement are obvious. Structured light technology has extremely high precision at short distancesusually within 1 meter), which can reach the sub-millimeter level, but the precision drops rapidly with increasing distance, and the measurement range is generally within few meters. If the AR/VR application mainly involves long-distance interaction, such as large-scale virtual scene exploration and outdoor AR navigation, ToF technology is suitable; if it focuses on short-distance fine operation and object modeling, such as jewelry design and cultural relics restoration AR applications, structured light technology can better meet requirements.

ToF technology has strong resistance to environmental light interference and can operate normally in both strong and weak light. Structured light technology is greatly affected by environmental light, and the projection pattern is easily submerged in strong light, resulting in a decrease in measurement precision or even to work. Therefore, ToF technology has a greater advantage when using AR/VR devices outdoors or in complex lighting environments; in relatively stable indoor lighting environments, structured technology can give full play to its high precision characteristics.

In general, ToF technology has a high degree of integration, and high-end dToF solutions require professional laser emission and reception chips, with relatively high costs. Some structured light technology solutions have great flexibility in hardware and different grades of projectors and cameras can be selected according to needs. In applications sensitive to cost, hardware can be reasonably configured to reduce cost. AR/VR pursuing high performance and high integration, such as high-end VR head-mounted displays, may choose ToF technology; cost-constrained devices with high requirements for-distance precision, such as some consumer-grade AR glasses, structured light technology may be a better choice.

ToF technology has a fast response speed and provides depth data in real-time, which places high demands on the system's data processing capabilities to quickly process a amount of real-time data. Structured light technology requires shooting multiple pattern images and complex algorithm processing, with relatively slow data acquisition and processing speeds, and there are limitations in interaction scenarios with extremely high real-time requirements. For scenarios requiring quick response, such as VR game interaction or AR real-time navigation, ToF can better meet the requirements; for tasks that are not as demanding on time, such as object modeling and scene reconstruction, the data processing speed of structured light technology can accepted.