ToF camera systems consist of an image sensor, image processing chip and modulated light source. In simple terms, these systems work by illuminating a scene with a modulated light source, and then measuring the phase shift of the wave that is reflected back. Since light has a constant speed, ToF cameras are able to calculate the distance to each point in the scene based on the time it took for that light to return to the camera. Rather than scanning an image line by line, a ToF camera system will illuminate the entire scene all at once and then measures phase shift in the light reflected back to the image sensor. This raw data can be captured quickly and the calculation required to derive the distance is relatively straightforward, with ToF cameras thus achieving extremely high frame rates (even beyond what human vision can discern). This means that unlike many other 3D vision arrangements, ToF allows 3D depth information to be extracted from a scene in real-time using embedded processors.
ToF camera module