How industrial stereo cameras work
To reveal the principle of industrial stereo camera, it is very simple to simplify its principle. We can do an experiment: hold a pen or chopsticks in both hands at the same time, close one eye, use only the other eye, and try to put the tips of the pen or chopsticks in both hands together. You'll find that doing this is harder than you think. One eye sees objects as two-dimensional images. Using visual cues provided by objects such as size and overlap, it can determine the order in which these objects are placed in front of the background, but it has no way of knowing how far apart they are.
Fortunately, the human visual system is based on two eyes. When two horizontally arranged eyes are looking at the same object, the images they see are slightly different due to the slightly different angles. This is called parallax. The two pictures are combined together and automatically synthesized and analyzed to form a deep vision. At the same time, the brain can also judge the depth and distance of the object according to the magnitude of the disparity between the same object in the two received images. The farther away from the eye, the smaller the disparity, and vice versa. This is the basic principle of industrial stereo camera.