Abstract: A three-dimensional sensing apparatus including a light-projecting device, at least two image-capture devices, and a processor is provided. The processor is electrically connected to the light-projecting device and the at least two image-capture devices and adapted to provide a control signal to the light-projecting device to adjust the intensity of the illumination beam. The processor adjusts the contrast of the captured image to form a contrast-enhanced image according to a first processing signal and extracts a feature region of the contrast-enhanced image to form a feature-extraction image according to a second processing signal. The processor normalizes the intensity of the feature-extraction image to form an optimized image according to a third processing signal and forms the optimized image into a depth image according to a sensing signal.