The function principle of the PMD technology is based on time-of-flight (ToF). The scene is illuminated by modulated, invisible infrared light and the reflected light hits the PMD sensor.
The range of up to 35 m in typical environments and up to 50 m on reflective objects ensures universal use. Each pixel on the PMD chip determines the distances to the scene from the phase shift between the transmitted and the received signal.
The integrated, active suppression of background illumination almost completely prevents saturation of the image sensor by extraneous light. That means that the PMD 3D sensor can be operated in bright sunlight up to 120 klx.