1. A device for generating depth information, comprising: a plurality of light sources, wherein each light source of the plurality of light sources emits a corresponding intensity light, and intensities of corresponding intensity lights emitted by the plurality of light sources are different from each other; an image capture unit; a control unit coupled to the plurality of light sources and the image capture unit for controlling the each light source of the plurality of light sources to emit the corresponding intensity light in turn, and controlling the image capture unit to capture a plurality of images corresponding to the plurality of light sources; and a processing unit coupled to the image capture unit for generating a plurality of depth information corresponding to the plurality of light sources according to the plurality of images corresponding to the plurality of light sources and a background image after the image capture unit captures the plurality of images corresponding to the plurality of light sources and the background image.