Let's review some concepts and technical information about depth cameras. Currently, common depth cameras on the market can be roughly divided into four categories: TOF, structured light, passive vision, and other technologies.

Several depth camera technology principles

1. Tof

The representative technologies of TOF depth cameras are: phase and time. These two technologies 

determine the depth information by calculating the phase difference/time difference of light reflection.

2. Structured light

Representative technologies of structured light depth cameras include: speckle, mask, grating, and line 

laser.

Principle of speckle technology: random dotted light spots are modulated by three-dimensional objects.

Principle of mask technology: mask emits structured light

Principle of grating technology: known striped gratings are modulated by three-dimensional objects.

Principle of line laser technology: laser is modulated by three-dimensional objects, triangulation principle

3. Passive vision

Representative technologies of passive vision technology include monocular and binocular.

Principle of monocular technology: deep learning and matching.

Principle of binocular technology: triangulation principle based on parallax matching.

Advantages and disadvantages of several depth cameras

1. TOF

TOF technology advantages: small size, high integration, low cost

TOF technology disadvantages: high power consumption, difficult to improve resolution accuracy

2. Structured light

Structured light technology advantages: using mature 2D sensors, rich and diverse products, suitable for 

different precisions and costs, especially dynamic structured light, which is even more accurate than other

technical schools.

Structured light technology disadvantages: restricted by depth of field and light intensity, long distance is

not ideal, and in terms of speed, because dynamic structured light requires multiple pictures, so the 

natural 3D imaging speed is limited.

3. Passive vision

Advantages of passive vision technology: not limited by outdoor light, suitable for different distances, low 

cost

Disadvantages of passive vision technology: poor accuracy for featureless objects.