Sensor Types

Differences between sensor types

3D Sensing Type	Example Sensors	Principle of Work	Limitations
Stereovision	Realsense D405	3D structure inferred from two 2D cameras separated by baseline distance. Similar to human 3D perception.	Error quickly grows with distance (quadratically). Baseline determines working range (minimal distance and accuracy). Problem with 3D estimation in texture-less area.
Active Stereovision (pattern projection)	Realsense D435/D455	Stereovision supported by pattern projection. Improves 3D estimation in low texture areas and supports stereo algorithms. Sensor doesn't expect particular pattern.	Supporting projection may not work at larger distances or in sunlight (in such case sensor still works like stereovision).
Neural Stereovision	ZED 2i, ZED-X, ZED-X Mini	Stereovision supported by neural depth estimation improving accuracy.	Improved but less predictable accuracy. Typically still performs worse in texture-less areas and at larger distances.
Time of Flight (ToF)	Kinect4A, Femto Bolt	3D measurement based on time required for emitted light signal and its return.	May have trouble with low reflectivity (like black) objects, strong ambient light (sunlight), reflective surfaces. Sensor potentially interferes with other ToF sensors.
Structured Light	MotionCam-3D	Sensor expects particular projected patterns and computes 3D from pattern deformation.	May have trouble with strong ambient light (like sunlight), reflective surfaces and black objects. Rapid pattern projections potentially interfere with other sensors.